.golangci.yml: remove deprecated gomnd

In order to remove warning:
The linter \"gomnd\" is deprecated (step 2) and deactivated.
It should be removed from the list of disabled linters.
https://golangci-lint.run/product/roadmap/#linter-deprecation-cycle

.golangci.yml

@@ -44,7 +44,6 @@ linters:
     - gochecknoinits
     - godox
     - goimports
-    - gomnd
     - gomodguard
     - gosec
     - rowserrcheck