Remove references to yaml-templates (dotnet#33089)

Author: rmarinho

eng/pipelines/ci-official.yml

@@ -69,9 +69,6 @@ extends:
       spotBugs:
         enabled: false
         justification: 'Failing with "Could not successfully find the java tool launcher"'
-      sourceRepositoriesToScan:
-        exclude:
-        - repository: yaml-templates
       suppression:
         suppressionFile: $(Build.SourcesDirectory)\eng\automation\guardian\source.gdnsuppress
     stages:

eng/pipelines/common/apiscan.yml

@@ -129,14 +129,6 @@ parameters:
     demands:
     - macOS.Name -equals Sequoia
 
-resources:
-  repositories:
-  - repository: yaml-templates
-    type: github
-    name: xamarin/yaml-templates
-    endpoint: xamarin
-    ref: refs/heads/main
-
 stages:
 
 - stage: build_net

eng/pipelines/common/sign.yml

@@ -86,9 +86,6 @@ extends:
       spotBugs:
         enabled: false
         justification: 'Failing with "Could not successfully find the java tool launcher"'
-      sourceRepositoriesToScan:
-        exclude:
-        - repository: yaml-templates
       suppression:
         suppressionFile: $(Build.SourcesDirectory)\eng\automation\guardian\source.gdnsuppress
     stages: