Canonicalise around 'Blueshirt' as a proper noun

Fixes srobo/tasks#1471.

Includes workaround for streetsidesoftware/cspell#6582 as we haven't upgraded cspell yet.

Author: PeterJCLaw

.spelling

@@ -8,8 +8,12 @@ Bittele
 !blue-shirt.
 !blue-shirts
 !blue-shirts.
-blueshirt
-blueshirts
+!blueshirt
+!blueshirt.
+!blueshirts
+!blueshirts.
+Blueshirt
+Blueshirts
 boldrewood
 Bolkiah
 Calday

_events/sr2022/virtual-tech-day-december.md

@@ -9,6 +9,6 @@ location: Discord
 
 Tech Days are opportunities for teams to spend a whole day working on their robot with lots of help available. They’re also an opportunity to see how other teams are doing or get more direct help with their robots.
 
-The aim of this day is to help teams out by having guaranteed presence from us blueshirts. We'll be around to answer questions about the competition, give kit support, assist with the microgames, and assist with strategy ideas.
+The aim of this day is to help teams out by having guaranteed presence from us Blueshirts. We'll be around to answer questions about the competition, give kit support, assist with the microgames, and assist with strategy ideas.
 
 Our SR2022 December Tech Day is being hosted on our Discord server.

_events/sr2022/virtual-tech-day-january.md

@@ -9,7 +9,7 @@ location: Discord
 
 Tech Days are opportunities for teams to spend a whole day working on their robot with lots of help available. They’re also an opportunity to see how other teams are doing or get more direct help with their robots.
 
-The aim of this day is to help teams out by having guaranteed presence from us blueshirts. We'll be around to answer questions about the competition, give kit support, and assist with strategy ideas.
+The aim of this day is to help teams out by having guaranteed presence from us Blueshirts. We'll be around to answer questions about the competition, give kit support, and assist with strategy ideas.
 
 ## Schedule
 

_events/sr2022/virtual-tech-day-march.md

@@ -9,7 +9,7 @@ location: Discord
 
 Tech Days are opportunities for teams to spend a whole day working on their robot with lots of help available. They’re also an opportunity to see how other teams are doing or get more direct help with their robots.
 
-The aim of this day is to help teams out by having guaranteed presence from us blueshirts. We'll be around to answer questions about the competition, give kit support, and assist with strategy ideas.
+The aim of this day is to help teams out by having guaranteed presence from us Blueshirts. We'll be around to answer questions about the competition, give kit support, and assist with strategy ideas.
 
 ## Schedule
 

_events/sr2023/virtual-tech-day-december.md

@@ -12,7 +12,7 @@ robot with lots of help available. They’re also an opportunity to see how othe
 teams are doing or get more direct help with their robots.
 
 The aim of this day is to help teams out by having guaranteed presence from us
-blueshirts. We'll be around to answer questions about the competition, give kit
+Blueshirts. We'll be around to answer questions about the competition, give kit
 support, assist with the microgames, and assist with strategy ideas.
 
 Our SR2023 December Tech Day is being hosted on our [Discord](https://studentrobotics.org/docs/team_admin/discord) server.

_posts/2015-04-28-bws-victorious-sr2015.md

@@ -10,7 +10,7 @@ description: >
 {% include figure.html
            url="https://www.flickr.com/photos/richardpbarlow/17291755395/in/pool-sr2015/"
            src="/images/content/blog/sr2015/everyone.jpg"
-           caption="All the competitors and blueshirts on the stands at Newbury Racecourse. Photograph courtesy of Rich Barlow." %}
+           caption="All the competitors and Blueshirts on the stands at Newbury Racecourse. Photograph courtesy of Rich Barlow." %}
 
 {% include figure.html
            class="right"

_posts/2018-12-10-sr2019-tech-days-confirmed.md

@@ -6,7 +6,7 @@ As was announced at Kickstart, we will be running some Tech Days during this
 competition year.
 
 Tech Days are opportunities for teams to make concentrated progress on their
-robots with help from highly-experienced blueshirts. They’re also an
+robots with help from highly-experienced Blueshirts. They’re also an
 opportunity to get technical help and to see how well teams are doing in
 comparison to other teams. Later Tech Days may feature mockups of the arena,
 enabling teams to test their robots in more realistic ways.

volunteer.html

@@ -60,7 +60,7 @@ <h3 class="text-center">Events</h3>
             Kickstart, Tech Days, and the competition all depend on a small army
             of volunteers to run effectively. Whether it's shepherding teams,
             manning the help-desk, running reception, or orchestrating the
-            matches; we're always eager for more blueshirts.
+            matches; we're always eager for more Blueshirts.
           </p>
         </div>
         <div class="column s-4-12">
@@ -86,7 +86,7 @@ <h2 class="text-center">Testimonials</h2>
       <div class="row">
         <div class="column s-4-12">
           <blockquote class="text-italic">
-            After one kickstart event, I was hooked, and haven’t looked back since! After finishing college, I just had to become a blueshirt, to help those like me realise their development potential too.
+            After one kickstart event, I was hooked, and haven’t looked back since! After finishing college, I just had to become a Blueshirt, to help those like me realise their development potential too.
           </blockquote>
           <p class="text-heavy text-center">— Jake Howard</p>
           <h5 class="text-center">