build(e2e): commit package-lock.json for the Playwright suite (#9199)

`e2e/` has been a Dependabot `npm` directory since #9089 but ships only a
`package.json` with a caret range. Without a lockfile every install
resolves whatever Playwright release is current, and Dependabot has to
guess the "from" version (#9098 was titled "1.63.0 -> 1.62.1" while it
actually raised the range from ^1.58.2).

- Add `e2e/package-lock.json` (lockfileVersion 3, public npm registry),
  resolving `@playwright/test` ^1.63.0 to 1.63.0. `package.json` is the
  npm-init scaffold and declares no `packageManager`, so npm is the
  natural tool; `**/*.json` is already excluded in `.licenserc.yaml`.
- Update the `/e2e` comment in `.github/dependabot.yml`: the directory
  now has a lockfile. `versioning-strategy: increase` stays, so the
  declared range and the locked version move together.

Signed-off-by: DoDiODev <DoDiDev@proton.me>

Author: DoDiODev

.github/dependabot.yml

@@ -102,8 +102,9 @@ updates:
     open-pull-requests-limit: 5
     commit-message:
       prefix: build(deps)
-    # This directory has no lockfile. Without `increase`, Dependabot would stay
-    # silent as long as a new release still satisfies the declared caret range.
+    # Raise the caret range in package.json together with package-lock.json so
+    # the declared minimum always matches the locked version. The default
+    # `auto` may classify this non-private package as a library and only widen.
     versioning-strategy: increase
     groups:
       e2e-minor-patch: