Fixes #7758: Fixed JWT token for Jitsi openidtoken-jwt authentication

[tomtit]

Type of change

• Feature
• Bugfix
• Technical
• Other :

Content

Used the hard-coded key from the module prosody-mod-auth-matrix-user-verification to sign the JWT for Jitsi openidtoken-jwt authentication to pass token validation at Prosody side.

Motivation and context

#7758

Screenshots / GIFs

Tests

• start a group video call
• get into the video call

Tested devices

• Physical
• Emulator
• OS version(s): Android 6.0, Android 10.0

Checklist

• Changes has been tested on an Android device or Android emulator with API 21
• UI change has been tested on both light and dark themes
• Accessibility has been taken into account. See https://github.com/vector-im/element-android/blob/develop/CONTRIBUTING.md#accessibility
• Pull request is based on the develop branch
• Pull request includes a new file under ./changelog.d. See https://github.com/vector-im/element-android/blob/develop/CONTRIBUTING.md#changelog
• Pull request includes screenshots or videos if containing UI changes
• Pull request includes a sign off
• You've made a self review of your PR
• If you have modified the screen flow, or added new screens to the application, you have updated the test UiAllScreensSanityTest.allScreensTest()

[langleyd]

I've looked over these changes and have tested them on an environment where I could reproduce the issue. Thanks for fix!

[bmarty]

Thanks @langleyd . I do not see how to trigger the CI again, but I think this is fine to merge the PR. I can handle issue if it breaks something.