lint: remove structcheck

structcheck is abandoned, and has been replaced by the unused linter.
See https://golangci-lint.run/usage/linters/#structcheck for more
information.

Signed-off-by: Justin Chadwell <me@jedevc.com>

.golangci.yml

@@ -21,7 +21,6 @@ linters:
     - revive
     - staticcheck
     - typecheck
-    - structcheck
   disable-all: true
 
 linters-settings: