feat(package): migrate to ng12

[asithade]

** PR Checklist Please check if your PR fulfills the following requirements:

• [ ] The commit message follows our guidelines: https://github.com/fulls1z3/ngx-cache/blob/master/CONTRIBUTING.md#commit
• [ ] Tests for the changes have been added (for bug fixes / features)
• [ ] Docs have been added / updated (for bug fixes / features)

** PR Type What kind of change does this PR introduce?

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

** What is the current behavior? The current build uses angular 9

Issue Number: #138 #136

** What is the new behavior? Allows packages to work with Angular 12

** Does this PR introduce a breaking change?

[x] Yes
[ ] No

** Other information

[ghost]

Sider has detected 2 warnings on analyzing the commit 69fa083.

• ⚠️ Goodcheck
• ⚠️ TSLint

We recommend fixing them as possible by updating the dependencies, configuring the analysis tool, configuring sider.yml, turning off unused tools, and so on.

If you have problems or questions still, feel free to ask us via chat. 💬

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[fulls1z3]

@asithade need help with these PR's, especially with ng-packagr is failing. once done aim is first to ng 10 and then eventually to ng11 and ng12 (supporting all intermediate versions)

• https://github.com/fulls1z3/ngx-meta/pull/216
• https://github.com/fulls1z3/ngx-config/pull/169
• https://github.com/fulls1z3/ngx-cache/pull/141
• https://github.com/fulls1z3/ngx-auth/pull/135

and finally we're showcasing it on https://github.com/fulls1z3/universal/pull/755