Move RequiresClient from MatrixCapabilities to ElementWidgetCapabilities

[rkouwenhoven]

This PR fixes element-hq/element-web#20920 by moving RequiresClient to the ElementWidgetCapabilities enum.
See also matrix-org/matrix-widget-api#54

I reopened this PR from #7935 to use a different branch.

Please add T-Task label.

Signed-off-by: Robin Kouwenhoven r.kouwenhoven@outlook.com

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This change is marked as an internal change (Task), so will not be included in the changelog.

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[codecov]

Codecov Report

Merging #8290 (471eaba) into develop (8eaae6b) will decrease coverage by 0.19%.
The diff coverage is n/a.

❗ Current head 471eaba differs from pull request most recent head 2f81bc8. Consider uploading reports for the commit 2f81bc8 to get more accurate results

@@             Coverage Diff             @@
##           develop    #8290      +/-   ##
===========================================
- Coverage    29.98%   29.79%   -0.20%     
===========================================
  Files          879      872       -7     
  Lines        50087    50006      -81     
  Branches     12747    12723      -24     
===========================================
- Hits         15017    14897     -120     
- Misses       35070    35109      +39     

Impacted Files	Coverage Δ
src/components/views/elements/AppTile.tsx	51.52% <ø> (ø)
src/stores/widgets/StopGapWidgetDriver.ts	0.00% <ø> (ø)
src/autocomplete/EmojiProvider.tsx	16.27% <0.00%> (-72.86%)	⬇️
src/autocomplete/AutocompleteProvider.tsx	0.00% <0.00%> (-60.72%)	⬇️
src/MatrixClientPeg.ts	12.94% <0.00%> (-17.40%)	⬇️
...ews/settings/tabs/room/SecurityRoomSettingsTab.tsx	0.00% <0.00%> (-0.76%)	⬇️
src/components/views/dialogs/InviteDialog.tsx	0.51% <0.00%> (-0.05%)	⬇️
src/RoomInvite.tsx	0.00% <0.00%> (ø)
src/settings/Settings.tsx	63.15% <0.00%> (ø)
src/settings/SettingsStore.ts	58.59% <0.00%> (ø)
... and 19 more

[turt2live]

Thanks!