travis ci migration to github action

[saheerb]

Summary of changes

mbed-os is migration basic CI checks currently done in Travis CI as Travis is not free anymore. This is a Draft PR to get some feedback on GiHub Action migration from travsi CI.

Testing is currently ongoing with this PR.

Impact of changes

No user impacted changes.

Migration actions required

Once merged in we shall disable CI for "mbed-os" from travis side.

Documentation

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Pull request type

[X] Patch update (Bug fix / Target update / Docs update / Test update / Refactor)
[] Feature update (New feature / Functionality change / New API)
[] Major update (Breaking change E.g. Return code change / API behaviour change)

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Test results

[] No Tests required for this change (E.g docs only update)
[X] Covered by existing mbed-os tests (Greentea or Unittest)
[] Tests / results supplied as part of this PR

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Reviewers

@jamesbeyond

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[ciarmcom]

@saheerb, thank you for your changes.
@jamesbeyond @ARMmbed/mbed-os-maintainers please review.

[0xc0170]

This file was completely removed, the functionality is already provided (or was anything ported from this script) ?

[saheerb]

Yea, this is no longer required as installation of gcc etc in directly in docker image. rest is replaced by apt install as needed.

[jamesbeyond]

LGTM

[Patater]

LGTM

[Patater]

CI started.

We don't expect results to be reported for Travis, as this PR removes .travis.yml.

[mbed-ci]

Jenkins CI Test : ✔️ SUCCESS

Build Number: 1 | 🔒 Jenkins CI Job | 🌐 Logs & Artifacts

CLICK for Detailed Summary

jobs	Status
jenkins-ci/mbed-os-ci_unittests	✔️
jenkins-ci/mbed-os-ci_cmake-cloud-example-ARM	✔️
jenkins-ci/mbed-os-ci_build-cloud-example-ARM	✔️
jenkins-ci/mbed-os-ci_build-cloud-example-GCC_ARM	✔️
jenkins-ci/mbed-os-ci_cmake-cloud-example-GCC_ARM	✔️
jenkins-ci/mbed-os-ci_build-greentea-ARM	✔️
jenkins-ci/mbed-os-ci_cmake-example-GCC_ARM	✔️
jenkins-ci/mbed-os-ci_build-greentea-GCC_ARM	✔️
jenkins-ci/mbed-os-ci_cmake-example-ARM	✔️
jenkins-ci/mbed-os-ci_build-example-GCC_ARM	✔️
jenkins-ci/mbed-os-ci_build-example-ARM	✔️
jenkins-ci/mbed-os-ci_greentea-test	✔️

[0xc0170]

I removed travis required check for master, I'll merge this in now.