chore: clean up and sort golangci-lint configuration

Signed-off-by: Matthieu MOREL <matthieu.morel35@gmail.com>

Author: mmorel-35

.golangci.yml

@@ -31,16 +31,12 @@ linters:
       formatter:
         require-f-funcs: true
   exclusions:
-    generated: lax
     presets:
       - comments
       - common-false-positives
       - legacy
       - std-error-handling
-    paths:
-      - third_party$
-      - builtin$
-      - examples$
+    warn-unused: true
 issues:
   max-issues-per-linter: 0
   max-same-issues: 0
@@ -52,9 +48,3 @@ formatters:
     goimports:
       local-prefixes:
         - github.com/prometheus/common
-  exclusions:
-    generated: lax
-    paths:
-      - third_party$
-      - builtin$
-      - examples$