Remove wp-scripts e2e toolchain

[dinhtungdu]

Started as a dependency update to address the Axios security issue. However, I noticed that we only have that package because it's a dependency of wp-script, and we only use wp-script for E2E testing. Our E2E test suite has only one simple test that can be covered by our PHP test. So, I decided to remove the ET test and all of the wp-script dependencies.

Testing:

• npm run lint:js ✅
• npm run test:php ✅
• Verify the built is identical:

# Verify built assets are identical to trunk
TRUNK_DIR="$(mktemp -d)"
trap 'rm -rf "$TRUNK_DIR"' EXIT
git clone --branch trunk --depth 1 --single-branch . "$TRUNK_DIR" 2>/dev/null
(cd "$TRUNK_DIR" && npm ci --silent 2>/dev/null && npm run build:dev --silent 2>/dev/null)
npm ci --silent 2>/dev/null && npm run build:dev --silent 2>/dev/null
diff -rq assets "$TRUNK_DIR/assets" && \
diff -q style.css "$TRUNK_DIR/style.css" && \
diff -q style-rtl.css "$TRUNK_DIR/style-rtl.css" && \
echo "✅ No differences" || echo "❌ Differences found"

Changelog:

Dev – Remove wp-scripts e2e tooling and cover the footer credit smoke test in PHP.

[gigitux]

I left few comments, but I'm pre-approving the PR. Thanks for working on this!