Use minimum required permissions for GitHub workflows

[triallax]

What is it?

• Meta improvement to the project (dev facing)

Description of the changes in your PR

Use minimum needed permissions for GitHub workflows and jobs. This reduces the attack surface if the workflows are ever compromised.

Due diligence

• I read the contribution guidelines.

[sonarqubecloud]

Kudos, SonarCloud Quality Gate passed!   

0 Bugs
0 Vulnerabilities
0 Security Hotspots
0 Code Smells

No Coverage information
No Duplication information

[triallax]

The SonarCloud failure is unrelated, this should be good to go.

[triallax]

We should also probably set the GITHUB_TOKEN permissions to "restrictive" on our existing repositories and on the organization as a whole: https://docs.github.com/en/actions/security-guides/automatic-token-authentication#permissions-for-the-github_toke

[litetex]

LGTM

@TobiGr @Stypox @TheAssassin
You may have a look at @mhmdanas last comment...

[litetex]

See also TeamNewPipe/NewPipeExtractor#869

[Stypox]

Now that we have manually specified permissions for each workflow, I made the default permissions read-only. Let's see if this works correctly...