Enable exportloopref linter

The linter does not report anything new, so we can enable it without any
other code changes.

Signed-off-by: Sascha Grunert <sgrunert@redhat.com>

.golangci.yml

@@ -32,6 +32,7 @@ linters:
     - errchkjson
     - errname
     - execinquery
+    - exportloopref
     - ginkgolinter
     - gocheckcompilerdirectives
     - gochecksumtype
@@ -90,7 +91,6 @@ linters:
     # - errorlint
     # - exhaustive
     # - exhaustruct
-    # - exportloopref
     # - forbidigo
     # - forcetypeassert
     # - funlen