Fix typescript peer dependency conflict and patch ruleTester

Author: plthomasva

.github/workflows/eslint-9+.yml

@@ -59,7 +59,7 @@ jobs:
           node-version: ${{ matrix.node-version }}
           after_install: |
             npm remove --no-save eslint-doc-generator
-            npm install --no-save "eslint@${{ matrix.eslint }}" "@typescript-eslint/parser@${{ matrix.eslint == 10 && 'canary' || (matrix.typescript-eslint == 8 && 8.17 || matrix.typescript-eslint) }}" "babel-eslint@${{ matrix.babel-eslint }}" "typescript@5"
+            npm install --no-save "eslint@${{ matrix.eslint }}" "@typescript-eslint/parser@${{ matrix.eslint == 10 && 'canary' || (matrix.typescript-eslint == 8 && 8.17 || matrix.typescript-eslint) }}" "babel-eslint@${{ matrix.babel-eslint }}" "typescript@5" --legacy-peer-deps
           skip-ls-check: true
       - run: npx ls-engines
       - run: npm run unit-test