Why:

* https://gitlab.com/gitlab-org/gitlab/-/issues/36059

This change addresses the need by:

* Remove references to TSLint.
* Update TypeScript references to point to the ESLint analyzer.
* Remove tslint-sast job from the SAST.gitlab-ci.yml file.
* Update eslint-sast job in the SAST.gitlab-ci.yml file to be triggered
  by TypeScript files.

Side effects:

* TypeScript vulnerabilities may be auto closed and reopened by the
  ESLint analyzer.