Remove probes with fail config

[proditis]

This PR introduces the following changes

• Display a clear error message when an unknown client driver is used
• Remove probers that are not configured properly, from probers[]
• Remove notifies that are not configured properly, from notifies[]
• Error out and (exit?) when there are no probers or notifies configured
• Update test cases to test for empty probers and notifies
• Update test case for config to use port 65535 instead of the more common 8080 to avoid conflicts with local development environments

[codecov-commenter]

Codecov Report

Merging #137 (89c9a8a) into main (1db0629) will increase coverage by 0.00%.
The diff coverage is 100.00%.

@@           Coverage Diff           @@
##             main     #137   +/-   ##
=======================================
  Coverage   91.40%   91.41%           
=======================================
  Files          43       43           
  Lines        2920     2923    +3     
=======================================
+ Hits         2669     2672    +3     
  Misses        180      180           
  Partials       71       71           

Impacted Files	Coverage Δ
probe/client/client.go	100.00% <100.00%> (ø)

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[haoel]

LGTM