Fix BackGrid Object formatter

[pierredup]

Fixes #784

[what-the-diff]

PR Summary

• ObjectFormatter is now a plain object
  The ObjectFormatter has been simplified by converting it from an ES6 class to a plain object.
• No longer extends Backgrid's CellFormatter
  Although it no longer extends Backgrid's CellFormatter, the same interface (fromRaw and toRaw) is still implemented.
• Removed lodash/noop and optimized lodash imports
  The unnecessary lodash/noop has been removed and lodash imports have been optimized to prevent bundle size increases from future dependencies.

[codecov]

Codecov Report

Patch coverage: 68.72% and project coverage change: +0.90 🎉

Comparison is base (6471077) 49.68% compared to head (91d6b7a) 50.58%.

Additional details and impacted files

@@             Coverage Diff              @@
##              2.3.x     #785      +/-   ##
============================================
+ Coverage     49.68%   50.58%   +0.90%     
- Complexity     2194     2205      +11     
============================================
  Files           438      437       -1     
  Lines          8276     8229      -47     
============================================
+ Hits           4112     4163      +51     
+ Misses         4164     4066      -98     

Flag	Coverage Δ
unittests	50.58% <68.72%> (+0.90%)	⬆️

Flags with carried forward coverage won't be shown. Click here to find out more.

Impacted Files	Coverage Δ
src/ApiBundle/ApiTokenManager.php	100.00% <ø> (ø)
...le/Event/Listener/AuthenticationSuccessHandler.php	0.00% <ø> (ø)
.../Normalizer/AdditionalContactDetailsNormalizer.php	94.73% <ø> (ø)
...undle/Serializer/Normalizer/DiscountNormalizer.php	100.00% <ø> (ø)
src/ClientBundle/Action/Add.php	0.00% <ø> (ø)
src/ClientBundle/Action/Ajax/Address/Edit.php	0.00% <ø> (ø)
src/ClientBundle/Action/Ajax/Contact/Add.php	0.00% <ø> (ø)
src/ClientBundle/Action/Ajax/Contact/Edit.php	0.00% <ø> (ø)
src/ClientBundle/Action/Ajax/Delete.php	0.00% <ø> (ø)
src/ClientBundle/Action/Edit.php	0.00% <ø> (ø)
... and 174 more

... and 4 files with indirect coverage changes

☔ View full report in Codecov by Sentry.
📢 Do you have feedback about the report comment? Let us know in this issue.