ci: Set golangci-lint run timeout to 5 minutes (#260)

Reference: https://github.com/hashicorp/terraform-plugin-docs/actions/runs/5191760369/jobs/9360009612
Reference: https://github.com/hashicorp/terraform-plugin-framework/blob/1e82228e6631748852c4cd00b6c7e1c0c1a4cfc2/.golangci.yml#L27-L29

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Author: bflad

.golangci.yml

@@ -22,4 +22,8 @@ linters:
     - unconvert
     - unparam
     - unused
-    - vet
+    - vet
+
+run:
+  # Prevent false positive timeouts in CI
+  timeout: 5m