github: explicitly set workflow permissions

[jku]

• current workflow only needs to read git content
• if the workflow in the future does need write access (or even other read access than the git repo), it's good to
  see permissions explicitly changing

For context: "pull_request" runs never have any write access anyway, so this
significantly changes only the "push" runs that happen when branches are
merged to develop.

Signed-off-by: Jussi Kukkonen jkukkonen@vmware.com

Fixes#1662

[coveralls]

Pull Request Test Coverage Report for Build 1420674927

• 0 of 0 changed or added relevant lines in 0 files are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage remained the same at 97.442%

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Totals
Change from base Build 1420270018:	0.0%
Covered Lines:	3946
Relevant Lines:	4030

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💛 - Coveralls

[jku]

For anyone wondering: you can see the permissions by going to the job logs, opening "Set up job", then opening "GITHUB_TOKEN Permissions"

[lukpueh]

Cross-checked with relevant GH docs. LGTM. Thanks, Jussi!

[coveralls]

Pull Request Test Coverage Report for Build 1420674927

Warning: This coverage report may be inaccurate.

This pull request's base commit is no longer the HEAD commit of its target branch. This means it includes changes from outside the original pull request, including, potentially, unrelated coverage changes.

• For more information on this, see Tracking coverage changes with pull request builds.
• To avoid this issue with future PRs, see these Recommended CI Configurations.
• For a quick fix, rebase this PR at GitHub. Your next report should be accurate.

Details

• 0 of 0 changed or added relevant lines in 0 files are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage increased (+1.1%) to 98.548%

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Totals
Change from base Build 1420270018:	1.1%
Covered Lines:	3116
Relevant Lines:	3129

---

💛 - Coveralls