feat: Removed phantomjs dependency

[ossdev07]

BREAKING CHANGE: Added support for chrome headless
Phantomjs is an unmaintained project, removed phantomjs dependency from package.json, karma.conf.js, and Makefile. Added chrome headless support in package.json, karma.conf.js, and Makefile.
package-lock.json file got updated whenever we run the package.

Signed-off-by: ossdev07 ossdev@puresoftware.com

[codecov]

Codecov Report

Merging #1204 into master will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master    #1204   +/-   ##
=======================================
  Coverage   94.51%   94.51%           
=======================================
  Files          32       32           
  Lines        1676     1676           
  Branches      404      404           
=======================================
  Hits         1584     1584           
  Misses         92       92

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[ossdev07]

Ping @keithamus @meeber

Can you please have a look at this PR.
It will be a delight to see phantomjs removed from chai.

[meeber]

Thanks @ossdev07. Seems like a good idea to me.

Pinging @chaijs/chai.

Edit: Regarding the commit message: I'd consider this chore instead of feat. Would also prefer to squash commits before or during merge.

[keithamus]

Agreed. Also not a breaking change - the code is still the same.

[ossdev07]

@keithamus @meeber

Thanks, for approving this PR.