ci: disable sonarcloud on forks

[julienrbrt]

Description

The issue is sonarcloud does not run on forks from external contributors.
This is what prohibited us to make the job of our components required.
This PR replicates cosmos/interchain-security#768.
I have purposely not added this logic our repo-analysis job as it makes no sense, as this job will never be required.

IMO, afterward, we should make all test-* required (cc @tac0turtle).

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Author Checklist

All items are required. Please add a note to the item if the item is not applicable and
please add links to any relevant follow up issues.

I have...

• included the correct type prefix in the PR title
• added ! to the type prefix if API or client breaking change
• targeted the correct branch (see PR Targeting)
• provided a link to the relevant issue or specification
• followed the guidelines for building modules
• included the necessary unit and integration tests
• added a changelog entry to CHANGELOG.md
• included comments for documenting Go code
• updated the relevant documentation or specification
• reviewed "Files changed" and left comments if necessary
• confirmed all CI checks have passed

Reviewers Checklist

All items are required. Please add a note if the item is not applicable and please add
your handle next to the items reviewed if you only reviewed selected items.

I have...

• confirmed the correct type prefix in the PR title
• confirmed ! in the type prefix if API or client breaking change
• confirmed all author checklist items have been addressed
• reviewed state machine logic
• reviewed API design and naming
• reviewed documentation is accurate
• reviewed tests and test coverage
• manually tested (if applicable)

[julienrbrt]

Could an admin make all these tests Tests / Code Coverage / test-* required after this PR?:

NOTE: Please wait before making test-store required, as it has been broken in the streaming PR (see #15399 (comment)). We should make it required once it is fixed.