Remove activeTab permission, which we don't need

  - The Chrome extension webstore now asks for justification for each
    permission, and I couldn't justify the activeTab permission because
    I didn't know how we used it. Turned out, that we don't, and so I
    removed it from both the Firefox and Chrome manifests

Author: fraz3alpha

browser-extensions/chrome/manifest.json

@@ -136,7 +136,6 @@
       "/css/*"
   ],
   "permissions": [
-    "activeTab",
     "storage",
     "https://www.parkrun.org.uk/",
     "https://wiki.parkrun.com/"

browser-extensions/firefox/manifest.json

@@ -139,7 +139,6 @@
       "/css/*"
   ],
   "permissions": [
-    "activeTab",
     "storage",
     "https://www.parkrun.org.uk/",
     "https://wiki.parkrun.com/"