Configure linter to forbid use of html/template

We should never use html/template due to the performance penalty and the fact that we are highly unlikely to ever be generating HTML templates.

.golangci.yml

@@ -76,6 +76,7 @@ linters-settings:
   forbidigo:
     # Forbid the following identifiers (list of regexp).
     forbid:
+      - '\bhtml\/template\b(# Use text/template instead)?'
       - '\bioutil\b(# Use io and os packages instead of ioutil)?'
       - '\brequire\.New\b(# Use package-level functions with explicit TestingT)?'
       - '\bassert\.New\b(# Use package-level functions with explicit TestingT)?'