update canale_digitale_link serializer

[luca-bellenghi]

DTD is asking to change the behavior when the 'access the service' button is pressed. They don't want to see 'unauthorized,' but rather they want an 'access' label, which can be obtained using /login. For this reason, we want to ensure that if the current user doesn't have permission to view the target of the 'access the service' button, a link with /login will be used instead.

[coveralls]

Pull Request Test Coverage Report for Build 10734992836

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.

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Details

• 7 of 7 (100.0%) changed or added relevant lines in 1 file are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage increased (+0.03%) to 69.331%

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Totals
Change from base Build 10697128893:	0.03%
Covered Lines:	3287
Relevant Lines:	4741

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💛 - Coveralls