Transifex change of URL

[sjib]

Description:
Starting April 3rd, 2023, the transifex web application's domain changes from www.transifex.com to app.transifex.com., while the API will remain unaffected.

For example, URLs such as:
www.transifex.com/my_example_organization/

and any URL related to this organization will be relocated to:

app.transifex.com/my_example_organization/

Transifex will automatically redirect all requests made to the old domain until July 3rd, 2023, so you can have enough time to update any links you are using or sharing.

Related issue:

• Transifex change of URL QGEP/QGEP#815
• Webapp domain change for transifex QGEP/docs#211

[ponceta]

Adapted everywhere