Merge branch 'fix-unitialized-constant-bool-expr' into 'master'

Fix uninitialized constant Elastic::BoolExpr

See merge request gitlab-org/gitlab!43671

ee/lib/elastic/latest/git_class_proxy.rb

@@ -120,7 +120,7 @@ module Elastic
           filter :blob, field: :oid
         end
 
-        bool_expr = Gitlab::Elastic::BoolExpr.new
+        bool_expr = ::Gitlab::Elastic::BoolExpr.new
         query_hash = {
           query: { bool: bool_expr },
           size: per,