fix: Omit default branch for GitLab repositories as it is not always 'master'

[mshaposhnik]

What does this PR do?

Fixes the GitLab file reading behavior, by omitting master branch name by default.

Screenshot/screencast of this PR

What issues does this PR fix or reference?

https://issues.redhat.com/browse/CRW-1929

How to test this PR?

Before PR: Accepting factory with GitLab repository, having default branch other than 'master' is failing;
After PR: Accepting factory with GitLab repository, having default branch other than 'master' is OK;

PR Checklist

As the author of this Pull Request I made sure that:

• The Eclipse Contributor Agreement is valid
• Code produced is complete
• Code builds without errors
• Tests are covering the bugfix
• The repository devfile is up to date and works
• Sections What issues does this PR fix or reference and How to test this PR completed
• Relevant user documentation updated
• Relevant contributing documentation updated
• CI/CD changes implemented, documented and communicated

Reviewers

Reviewers, please comment how you tested the PR when approving it.

Release Notes Text

Unable to create a workspace using a factory link to an on-premise GitLab repository

Eclipse Che was unable to create a workspace using a factory link to an on-premise GitLab repository without a branch named `master.

[che-bot]

❌ E2E Happy path tests failed ❗

See Details

• Jenkins job

• test report

• logs and configs

• Happy path tests DevFile

• image: quay.io/crw_pr/che-server:34

Test product:

• tested with Eclipse Che on K8S (minikube v1.1.1)
• E2E test scenario
• E2E test pipeline source code

• Use comment "[crw-ci-test]" to rerun happy path E2E test.
• Use comment "[crw-ci-test --rebuild]" to re-build the images and rerun happy path E2E test.

Eclipse Che QE channel: https://mattermost.eclipse.org/eclipse/channels/eclipse-che-qe

[che-bot]

✅ E2E Happy path tests succeed 🎉

See Details

• Jenkins job

• test report

• logs and configs

• Happy path tests DevFile

• image: quay.io/crw_pr/che-server:34

Test product:

• tested with Eclipse Che on K8S (minikube v1.1.1)
• E2E test scenario
• E2E test pipeline source code

• Use comment "[crw-ci-test]" to rerun happy path E2E test.
• Use comment "[crw-ci-test --rebuild]" to re-build the images and rerun happy path E2E test.

Eclipse Che QE channel: https://mattermost.eclipse.org/eclipse/channels/eclipse-che-qe

[l0rd]

@mshaposhnik is there any issue associated to this PR? I am asking because we would like to add it to the release notes of 7.32 (and CRW 2.10).

[mshaposhnik]

@lord it came from CRW testing, so i have only this: https://issues.redhat.com/browse/CRW-1929

[l0rd]

@mshaposhnik cool thanks

[che-bot]

❌ E2E Happy path tests failed ❗

See Details

• Jenkins job

• test report

• logs and configs

• Happy path tests DevFile

• image: quay.io/crw_pr/che-server:34

Test product:

• tested with Eclipse Che on K8S (minikube v1.1.1)
• E2E test scenario
• E2E test pipeline source code

• Use comment "[crw-ci-test]" to rerun happy path E2E test.
• Use comment "[crw-ci-test --rebuild]" to re-build the images and rerun happy path E2E test.

Eclipse Che QE channel: https://mattermost.eclipse.org/eclipse/channels/eclipse-che-qe

[MichalMaler]

https://issues.redhat.com/browse/CRW-1962