ci: sync golangci-lint config

Author: caarlos0

.golangci.yml

@@ -33,6 +33,9 @@ linters:
     generated: lax
     presets:
       - common-false-positives
+  settings:
+    exhaustive:
+      default-signifies-exhaustive: true
 issues:
   max-issues-per-linter: 0
   max-same-issues: 0