Raise AuthorizationError on missing agent token

[joshmeek]

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• adds new tests (if appropriate)
• updates CHANGELOG.md (if appropriate)
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What does this PR change?

Adds an exception raise if no agent API token is provided
Closes #1454

Why is this PR important?

Helps avoid cases where an agent can deploy flows without providing an API token

[codecov]

Codecov Report

Merging #1459 into master will decrease coverage by 0.06%.
The diff coverage is 70%.

[cicdw]

This looks really good @joshmeek ; only question I have is whether we want to raise an error if a token other than RUNNER token is provided?

[joshmeek]

@cicdw We could do that, would require us to use something like PyJWT to decode the token and check the role

[jlowin]

@joshmeek you could query

query {
  authInfo {
    apiTokenScope
  }
}

[joshmeek]

@jlowin Oh awesome! I'll add that

[joshmeek]

@cicdw @jlowin PR became a lot bigger because I added a new fixture for the agent tests regarding the RUNNER token. This allowed me to remove a temporary config from almost all of the tests :)

[cicdw]

Just a question, def not requesting a change just want to make sure we cover any edge cases