Update url for Matrix Login to match Matrix Spec v1.13

[MTRNord]

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Description

This updates the endpoint version to match the current matrix spec. R0 has been gone since multiple matrix versions and should not be used anymore. See https://spec.matrix.org/v1.13/client-server-api/#post_matrixclientv3login for current spec.

Type of change

Please delete any options that are not relevant.

• Other

Checklist

• My code follows the style guidelines of this project
• I ran ESLint and other linters for modified files
• I have performed a self-review of my own code and tested it
• I have commented my code, particularly in hard-to-understand areas (including JSDoc for methods)
• My changes generates no new warnings
• My code needed automated testing. I have added them (this is optional task)

Screenshots (if any)

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[CommanderStorm]

Thanks

[CommanderStorm]

no idea why CI is failing. Definitively unrelated though ^^

Will debug later in th week, if nessesary