Deprecate/Remove older serverless runtime versions

[kwiatekus]

Description

The following runtime version will soon become stale:

• node.js v16 - remove from a list of supported runtimes.
• node.js v18 - deprecate
• pyton 3.9 - deprecate

AC

• Deprecated versions are marked as deprecated in kyma dashboard
• Deprecated versions are marked as deprecated in kyma CLI
• Update documentation
• Users cannot create nodejs v16 functions
• Users do not loose their existing nodejs v16 function - those keep running but cannot be edited unless runtime filed is changed.

Reasons

We want to stop users from selecting runtimes that are soon to be EOL or are close to it.
https://nodejs.org/en/about/previous-releases

Attachments
Blocked by #745 and #746

Reference issues from the past. Be mindful it was still before modularization
kyma-project/kyma#17701
kyma-project/kyma#17700

[halamix2]

Nodejs16 removal in order:

• chore: Remove Nodejs16 environment cli#1985
• Remove Nodejs16 support hydroform#447
• Remove Nodejs16 #810
• Remove Nodejs16 image test-infra#10056
• Remove Nodejs16 image #809

[halamix2]

Nodejs18 deprecation:

• chore: Deprecate Nodejs18 environment cli#2005
• chore: Deprecate Nodejs18 environment #827

[halamix2]

Python 3.9 was marked as deprecated, in Serverless and CLI repos