feat: improve error handling within startCallback and endCallback

[tehraven]

• This is a bugfix
• This is a feature
• This is a code refactor
• This is a test update
• This is a docs update
• This is a metadata update

For Bugs and Features; did you add new tests?

Yes - added a test where a misconfigured devServer option will cause a error to be thrown. This is now caught and handled in the startCallback.

Motivation / Use-Case

The startCallback (and stopCallback) helpers in this version are implementing Promise.then rejected callback param (Promise.then(success, error)), but they aren't actually catching errors that occur in the process of start and stop.

This change makes the util handle errors that occur from start, or downstream from start, making the utility a bit more helpful.

You can also see places in this repo's examples where startCallback expects to see an error and log it to the console, but prior to this change, thrown errors would not be handled nor logged in this way.

Breaking Changes

Additional Info

[linux-foundation-easycla]

The committers are authorized under a signed CLA.

• ✅ Anthony M. Powers (27d8518, 74ce319)

[codecov]

Codecov Report

Merging #3969 (74ce319) into master (8f66c22) will increase coverage by 0.01%.
The diff coverage is 100.00%.

@@            Coverage Diff             @@
##           master    #3969      +/-   ##
==========================================
+ Coverage   92.58%   92.59%   +0.01%     
==========================================
  Files          14       14              
  Lines        1362     1364       +2     
  Branches      474      474              
==========================================
+ Hits         1261     1263       +2     
  Misses         93       93              
  Partials        8        8              

Impacted Files	Coverage Δ
lib/Server.js	93.87% <100.00%> (+0.01%)	⬆️

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[alexander-akait]

@tehraven Big thanks, release will be on the next week, we need finish #3940