Audit only production dependencies

Security checks have been failing for months due to Vue CLI dependencies
and lack of resolution from the developers. This commit makes auditing
ignore development dependencies.

The reasons include:

- Vulnerabilities in developer dependencies cause pipelines to fail
  on every run.
- This is caused by dependencies such that lack resolution from the
  developers. Vue developers consider `npm audit` broken design and do
  not prioritize solutions. Discussions: vuejs/vue-cli#6637,
  vuejs/vue-cli#6621, vuejs/vue-cli#6555, vuejs/vue-cli#6553,
  vuejs/vue-cli#6523, vuejs/vue-cli#6486, vuejs/vue-cli#6632.
- Development packages are not relevant for the production payload.
- False positives create behavior of ignoring them completely instead of
  taking action, which creates a security vulnerability itself.
- Failed tests are shown in a badge on README file, giving wrong picture
  of security posture of users.

`npm audit --omit=dev` is used instead of `npm audit --production` which
is deprecated as of npm v8.7.0 npm/cli#4744.

.github/workflows/checks.security.yaml

@@ -19,4 +19,4 @@ jobs:
         uses: ./.github/actions/setup-node
       -
         name: NPM audit
-        run: exit "$(npm audit)" # Since node 15.x, it does not fail with error if we don't explicitly exit
+        run:  exit "$(npm audit --omit=dev)" # Since Node 15.x, it does not fail with error if we don't explicitly exit