docs: extend deprecation target for non-TLS API

[thaJeztah]

relates to:

• docs: deprecate TCP connection without TLS #4928
• Deprecate Docker API over TCP without TLS moby/moby#36357

No work has started yet on the deprecation, so extending the time- window.

- A picture of a cute animal (not mandatory but encouraged)

[thaJeztah]

This test is really flaky or there's some bug lurking somewhere;

#20 65.15 === FAIL: cli/connhelper/commandconn TestCloseRunningCommand (5.00s)
#20 65.15     commandconn_unix_test.go:57: assertion failed: 5 (int) != 0 (n int)
#20 65.15     commandconn_unix_test.go:58: assertion failed: error is not nil: write |1: broken pipe
#20 65.15     commandconn_unix_test.go:69: test did not finish in time

[codecov-commenter]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 61.73%. Comparing base (70118ae) to head (e9c0fc3).
Report is 2 commits behind head on master.

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #5150      +/-   ##
==========================================
- Coverage   61.76%   61.73%   -0.04%     
==========================================
  Files         297      294       -3     
  Lines       20761    20756       -5     
==========================================
- Hits        12824    12813      -11     
- Misses       7021     7024       +3     
- Partials      916      919       +3