[confignet] Add DialerTimeout config option

[TylerHelmuth]

Description:
Adds a new dialer_timeout config option to confignet to allow configuring the timeout of the connection.

Link to tracking Issue:
Closes #4331

Testing:
Added new unit tests

Documentation:
Updated readme

[codeboten]

Thanks for submitting this, I was looking at this Friday, and I'm curious what your thoughts are around whether or not this feature will allow the removal of dialer timeouts configuration in other components.

please take a look at the failing tests

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Comparison is base (9b6a18b) 91.49% compared to head (78991d1) 91.47%.
Report is 45 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #9066      +/-   ##
==========================================
- Coverage   91.49%   91.47%   -0.03%     
==========================================
  Files         316      320       +4     
  Lines       17181    17187       +6     
==========================================
+ Hits        15720    15722       +2     
  Misses       1165     1165              
- Partials      296      300       +4     

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[TylerHelmuth]

I'm curious what your thoughts are around whether or not this feature will allow the removal of dialer timeouts configuration in other components.

If a component already allowed configuring a dialer_timeout then they must already be doing their own net.DialTimeout, circumventing TCPAddr.Dial/NetAddr.Dial, so they can take advantage of their timeout value. In these cases I suspect the TCPAddr and NetAddr are only being used for their config and not their methods.

The carbonexporter is an example of a Contrib component that does this.

It looks like the signalfx exporter also does this: https://github.com/open-telemetry/opentelemetry-collector-contrib/blob/95cb7336823185453e7a6538dc38988ee6596042/exporter/signalfxexporter/internal/dimensions/dimclient.go#L92-L96. But in this case they also take advantage of additional net.Dialer settings that confignet does not support.

This kinda gets to a question about how much of a wrapper confignet needs to be.