Replace lint-go-gopls with additional govet linters (#36028)

Many (but not all) analyzers ran by `gopls check` are available in
`golangci-lint` as part of default-disabled `govet` linters, so I think
it's best we remove this manual linting step and let `golangci-lint`
handle it. I hand-picked two available linters that were previously
linted using gopls and this list is not exhaustive.

This will reduce CI time by about 3 minutes.

.golangci.yml

@@ -114,6 +114,10 @@ linters:
         - stringsbuilder
     perfsprint:
       concat-loop: false
+    govet:
+      enable:
+        - nilness
+        - unusedwrite
   exclusions:
     generated: lax
     presets: