cirrus: save/restore golangci-lint cache for linux

This shaves off some time (40 seconds, ~15%) from a validate job
(unless either golangci-lint or go version changes).

The cache size is pretty small (currently 686Kb compressed).

Signed-off-by: Kir Kolyshkin <[email protected]>

Author: kolyshkin

.cirrus.yml

@@ -59,6 +59,12 @@ validate_task:
         image_name: ${DEBIAN_CACHE_IMAGE_NAME}
     env:
         HOME: "/root"  # default unset, needed by golangci-lint.
+    golangci-lint_cache:
+        folder: /root/.cache/golangci-lint
+        reupload_on_changes: true
+        fingerprint_script:
+            - go version
+            - grep GOLANGCI_LINT_VERSION Makefile | head -1
     script: |
         git remote update
         make tools

.golangci.yml

@@ -14,5 +14,5 @@ linters:
   exclusions:
     presets:
       - comments
-      - common-false-positives
+      #      - common-false-positives
       - std-error-handling