fix: restore "v" prefix for golangci-lint version in CI workflows

The golangci-lint-action v9.2.0 requires version strings in "vX.Y.Z" format.
Previous attempt to remove the "v" prefix caused validation error:
"invalid version string '1.64.5', expected format v1.2 or v1.2.3"

Updated both ci-pipeline.yml and quality-checks.yml to use "v1.64.5"
instead of "1.64.5" to match the action's expected format.

Fixes: #666 (PR CI validation failure)

.github/workflows/ci-pipeline.yml

@@ -75,7 +75,7 @@ jobs:
       - name: Run golangci-lint (fast)
         uses: golangci/golangci-lint-action@1e7e51e771db61008b38414a730f564565cf7c20 # v9.2.0
         with:
-          version: 1.64.5
+          version: v1.64.5
           working-directory: backend
           args: --config=.golangci-fast.yml --timeout=2m
 

.github/workflows/quality-checks.yml

@@ -75,7 +75,7 @@ jobs:
       - name: Run golangci-lint
         uses: golangci/golangci-lint-action@1e7e51e771db61008b38414a730f564565cf7c20 # v9.2.0
         with:
-          version: 1.64.5
+          version: v1.64.5
           working-directory: backend
           args: --config=.golangci-fast.yml --timeout=2m