fix: (menu & menuitem): vertical menu theming updates

[jaanus03]

The aim of this this PR is to update vertical menu styles to make it look great again.

Current vertical menu styles:

New vertical menu styles:

[codecov]

Codecov Report

Merging #934 into master will decrease coverage by 0.05%.
The diff coverage is 20%.

@@            Coverage Diff             @@
##           master     #934      +/-   ##
==========================================
- Coverage    81.5%   81.45%   -0.06%     
==========================================
  Files         673      673              
  Lines        8700     8708       +8     
  Branches     1541     1484      -57     
==========================================
+ Hits         7091     7093       +2     
- Misses       1594     1600       +6     
  Partials       15       15

Impacted Files	Coverage Δ
.../src/themes/teams/components/Menu/menuVariables.ts	66.66% <ø> (ø)	⬆️
packages/react/src/components/Menu/Menu.tsx	84.9% <ø> (ø)	⬆️
packages/react/src/components/Menu/MenuDivider.tsx	100% <ø> (ø)	⬆️
...kages/react/src/themes/teams-dark/siteVariables.ts	100% <ø> (ø)	⬆️
.../themes/teams/components/Menu/menuDividerStyles.ts	18.18% <0%> (-4.05%)	⬇️
...ms-high-contrast/components/Menu/menuItemStyles.ts	11.76% <0%> (-4.91%)	⬇️
...act/src/themes/teams/components/Menu/menuStyles.ts	13.04% <0%> (-4.35%)	⬇️
...src/themes/teams/components/Menu/menuItemStyles.ts	8.27% <0%> (ø)	⬆️
...themes/teams-dark/components/Menu/menuVariables.ts	100% <100%> (+50%)	⬆️
...ams-high-contrast/components/Menu/menuVariables.ts	100% <100%> (+50%)	⬆️
... and 1 more

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[bmdalex]

nice changes, some comments to address

[bmdalex]

@jaanus03

I found some time to take the branch and test it. It's true that the Dark and HC themes are much better, but we have a lot of regression on the general theme..

1. wrong fonts for regular theme (master vs your branch):

2. underlined menus styles broken:

3. primary underlined menus styles COMPLETELY broken:

4. iconOnly menus styles broken:

5. vertical pointing menus focused state broken:

6. focus outline broken for horizontal (no vertical prop) menus:

7. even in HC this TabList menu should have other colors I think:

@codepretty could you help validating some of these, I know you we're keeping a close eye on menus

[layershifter]

I think that issue with fonts comes from #950 and will be fixed by #951.

[codepretty]

Looks like the menu of the doc site was changed

@levithomason do you know how @jaanus03 can exclude his changes from affecting the left rail menu?

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Update: chatted with @levithomason about this and he says it is fine to check in

[codepretty]

Hover and keyboard focus background colors are supposed to be different

Comments were resolved