fix(core): showing/hiding column shouldn't affect its freezing position

[ghiscoding]

• when calling "hide column" we need to readjust the freezingColumn by (-1) when on left container
• when showing/hiding a column from ColumnPicker/GridMenu, we need to check if we need to also readjust when column is on the left container

TODOs

• add all Jest unit tests
• add Cypress E2E test
• requires core SlickGrid PR #561 to be merged & released

[codecov]

Codecov Report

Merging #185 (1cddb3e) into master (e7db0fd) will not change coverage.
The diff coverage is 100.00%.

@@            Coverage Diff            @@
##            master      #185   +/-   ##
=========================================
  Coverage   100.00%   100.00%           
=========================================
  Files          202       202           
  Lines        11710     11743   +33     
  Branches      3841      3856   +15     
=========================================
+ Hits         11710     11743   +33     

Impacted Files	Coverage Δ
...ges/common/src/extensions/columnPickerExtension.ts	100.00% <100.00%> (ø)
packages/common/src/extensions/extensionUtility.ts	100.00% <100.00%> (ø)
...ackages/common/src/extensions/gridMenuExtension.ts	100.00% <100.00%> (ø)
...kages/common/src/extensions/headerMenuExtension.ts	100.00% <100.00%> (ø)
packages/common/src/services/shared.service.ts	100.00% <100.00%> (ø)
...bundle/src/components/slick-vanilla-grid-bundle.ts	100.00% <100.00%> (ø)

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