🌱 Setup branding to be configurable during the build (#1664, #1742)

[github-actions]

Summary

Refactor and enhance branding capabilities. Now branding is included
from a single directory that contains at least strings.json,
manifest.json, and favicon.ico. Any other assets may be placed in
the directory and will be copied to the bundled app.

Running the build as normal should show no difference.

Running the build with BRANDING=./some-other-brand npm run start:dev
will try to use a branding from the specified directory (that is relative to the
project's source root).

See BRANDING.md for more details.

Resolves: #1682

Details

Branding changes:

• Move Konveyor branding assets to a project top-level branding directory

• Remove MTA branding assets

• Remove profile/branding constants from env and client module

• Embed branding strings and assets in the common module

  • strings.json is templated to allow the build to adjust asset
    URL path roots as necessary
  • brandingAssetPath()

• server's index.html generation sources the template strings from the
  common module's branding strings

• HeaderApp and AppAboutModal components support branding by using
  the useBranding hook

• BRANDING as a relative path is computed from the project root

• webpack build source branding assets directly from the common module

• Unit tests, snapshots and jest configs updated as necessary

Jest changes:

• Use react-i18next mock from client/__mocks__ as a more robust mock
  borrowed from react-i18n repos

• Move setupTests.ts into client/src/app/test-config to keep jest
  test config code all in the same directory

Related changes:

• Upgrade rollup to v4, add new rollup plugins (copy, virtual)

Downgrade to rollup v3 for multiarch builds (#1742)

As a followup on PRs #1664 and #1739, it became necessary to downgrade
back to rollup@^3.0. The v4 of rollup has "native" code that runs the build, and
that code does not currently work with s390 builds [1]. Since konveyor is built
for x86, arm, ppc, and s390, all of those need to work.

When the s390 builds can work with the wasm bits, we can upgrade to
rollup@^4.0 again.

[1] - rollup/rollup#5354

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Signed-off-by: Scott J Dickerson [email protected]
Co-authored-by: Ian Bolton [email protected]
Signed-off-by: Cherry Picker [email protected]

[ibolton336]

Probably will have to get this in for 7.0.3 since it is a non-blocker.

[sjd78]

I'll setup a full backport with this PR and #1742 rolled together.

[sjd78]

Reopening for v0.3.1

I'll update the github actions files to current for the release-0.3 branch in another PR.