Fix Integration tests for Big endian on GA CI

[sangitanalkar]

What's the problem this PR addresses?

Fixes the GA CI Integration jobs failing for Big endian.

How did you fix it?

1. Changed multiarch image to tonistiigi/binfmt:latest for running Big Endian tests as the tests failed in multiarch/qemu-user-static image.
   Note: All tests passed on s390x host VM, issues were seen in multiarch/qemu-user-static image.
   Tested running Integration tests using tonistiigi/binfmt:latest and all Big Endian Integration tests have passed.

2. Increased TEST_TIMEOUT for Big Endian to fix TC's failing due to timeout issue:

Checklist

• I have read the Contributing Guide.

• I have set the packages that need to be released for my changes to be effective.

• I will check that all automated PR checks pass before the PR gets reviewed.

[sangitanalkar]

@arcanis Could you please help in reviewing and merging this PR. Thank you!