ci: build golangci-lint from source to support Go 1.25

Use install-mode: goinstall to build golangci-lint using the project's
Go version (1.25) instead of using pre-built binaries built with Go 1.24.

Signed-off-by: Jose Alekhinne <alekhinejose@gmail.com>

Author: josealekhine

.github/workflows/ci.yml

@@ -43,5 +43,7 @@ jobs:
       - name: Run golangci-lint
         uses: golangci/golangci-lint-action@v6
         with:
-          version: latest
+          version: v1.64.8
           args: --timeout=5m
+          # Build golangci-lint from source using Go 1.25
+          install-mode: goinstall