add Erik and Taus as QL-for-QL reviewers

Author: erik-krogh

CODEOWNERS

@@ -25,3 +25,6 @@
 /docs/codeql-for-visual-studio-code/ @github/codeql-vscode-reviewers
 /docs/ql-language-reference/ @github/codeql-frontend-reviewers
 /docs/query-*-style-guide.md @github/codeql-analysis-reviewers
+
+# QL for QL reviewers
+/ql/ @erik-krogh @tausbn