[9.0] test: add submit and match test

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This PR adds a new github action workflow, that submits a job (to lbcertifdirac70) and then runs a pilot that tries to match a job. Few notes:

• uses github actions secrets
• retrieves a user proxy for submitting and running the job
• the job is simplest "echo Hello World" JDL (no dirac-jobexec)
• submits to and runs at site "DIRAC.CI.org"
• the client used for submitting the job and the DIRAC version installed by the pilot are of course a pip-install of the branch under test

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By adding these branches, we are basically restricting the run of this workflow only after the merge is made.
If a developer wants to run this, these branches should be removed, and the secrets added to the fork.

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Will be replaced by an integration test similar to #7570