Cleanup golangci-lint errcheck (#3502)

Move the errcheck excludes list from an external file to inline in the
golangci-lint config file.

Signed-off-by: SuperQ <superq@gmail.com>

.golangci.yml

@@ -30,7 +30,18 @@ linters-settings:
       - github.com/stretchr/testify/assert: "Use github.com/stretchr/testify/require instead of github.com/stretchr/testify/assert"
       - github.com/go-kit/kit/log: "Use github.com/go-kit/log instead of github.com/go-kit/kit/log"
   errcheck:
-    exclude: scripts/errcheck_excludes.txt
+    exclude-functions:
+      # Don't flag lines such as "io.Copy(io.Discard, resp.Body)".
+      - io.Copy
+      # The next two are used in HTTP handlers, any error is handled by the server itself.
+      - io.WriteString
+      - (net/http.ResponseWriter).Write
+      # No need to check for errors on server's shutdown.
+      - (*net/http.Server).Shutdown
+      # Never check for logger errors.
+      - (github.com/go-kit/log.Logger).Log
+      # Never check for rollback errors as Rollback() is called when a previous error was detected.
+      - (github.com/prometheus/prometheus/storage.Appender).Rollback
   goimports:
     local-prefixes: github.com/prometheus/alertmanager
   gofumpt:

scripts/errcheck_excludes.txt

@@ -1,13 +0,0 @@
-// Don't flag lines such as "io.Copy(io.Discard, resp.Body)".
-io.Copy
-// The next two are used in HTTP handlers, any error is handled by the server itself.
-io.WriteString
-(net/http.ResponseWriter).Write
-// No need to check for errors on server's shutdown.
-(*net/http.Server).Shutdown
-
-// Never check for logger errors.
-(github.com/go-kit/log.Logger).Log
-
-// Never check for rollback errors as Rollback() is called when a previous error was detected.
-(github.com/prometheus/prometheus/storage.Appender).Rollback