Upgrade to Angular 16

Issue type

I'm submitting a ... (check one with "x")

• bug report
• feature request
• question about the decisions made in the repository

Issue description

Current behavior: I noticed that ngx-admin was upgraded to Angular 15 and not Angular 16 is there any reason that ngx-admin is not using Angular 16 or should we except the upgrade anytime soon? @denStrigo

Expected behavior:

Steps to reproduce:

Related code:

insert short code snippets here

Other information:

npm, node, OS, Browser

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Angular, Nebular

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