chore(project): remove deprecated TSLint plugin recommendation

[saxicek]

Please check if the PR fulfills these requirements

• [x] The commit message follows our guidelines: https://github.com/moribvndvs/ng2-idle/blob/master/CONTRIBUTING.md#pr
• [ ] Tests for the changes have been added (for bug fixes / features)
• [ ] Docs have been added / updated (for bug fixes / features)

What kind of change does this PR introduce? (check one with "x")

[ ] Bugfix
[ ] Feature
[ ] Code style update (formatting, local variables)
[ ] Refactoring (no functional changes, no api changes)
[ ] Build related changes
[ ] CI related changes
[x] Other... Please describe: update of VSCode recommended plugins

What is the current behavior? (You can also link to an open issue here) Project recommends VSCode plugin TSLint which is now deprecated

What is the new behavior? Plugin recommendation is removed.

Does this PR introduce a breaking change? (check one with "x")

[ ] Yes
[x] No

If this PR contains a breaking change, please describe the impact and migration path for existing applications: ...

Other information: