feat(exception-group): Add new mechanism fields to Exception interface

[malwilley]

Mirrors the properties added in getsentry/relay#2020

Without this change the event endpoints will strip these values.

[codecov]

Codecov Report

Merging #47643 (149742c) into master (5b1edbc) will decrease coverage by 0.24%.
The diff coverage is 100.00%.

Additional details and impacted files

@@            Coverage Diff             @@
##           master   #47643      +/-   ##
==========================================
- Coverage   80.76%   80.52%   -0.24%     
==========================================
  Files        4765     4763       -2     
  Lines      201451   201243     -208     
  Branches    11617    11617              
==========================================
- Hits       162699   162058     -641     
- Misses      38496    38929     +433     
  Partials      256      256              

Impacted Files	Coverage Δ
static/app/components/actions/resolve.tsx	68.85% <ø> (+1.66%)	⬆️
static/app/components/modals/commandPalette.tsx	100.00% <ø> (ø)
...nents/modals/dashboardWidgetQuerySelectorModal.tsx	95.23% <ø> (+4.32%)	⬆️
static/app/components/modals/demoEndModal.tsx	60.00% <ø> (+2.37%)	⬆️
static/app/components/modals/demoSignUp.tsx	0.00% <ø> (ø)
...app/components/modals/inviteMembersModal/index.tsx	92.91% <ø> (+0.54%)	⬆️
...modals/savedSearchModal/createSavedSearchModal.tsx	79.16% <ø> (-0.84%)	⬇️
...atic/app/components/modals/suggestProjectModal.tsx	65.78% <ø> (+4.81%)	⬆️
static/app/components/modals/widgetViewerModal.tsx	77.68% <ø> (+0.48%)	⬆️
...modals/widgetViewerModal/widgetViewerTableCell.tsx	75.36% <ø> (-1.03%)	⬇️
... and 37 more

... and 35 files with indirect coverage changes