Collaborators form: Change default selection to 'maintainer'

[nlhkabu]

From user testing:

On the management collaborators page (manage/project/<projectname>/collaboration/) - we have a form to add a new owner or maintainer:

Currently, the default selected value is 'owner' - we should change the order, so that the default value is 'maintainer'.

Reason: Adding a maintainer is less dangerous :)

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[nlhkabu]

For consistency, we should also change the order of the information above the table, so that maintainer is listed first.

Related to #3157

[brainwane]

@aalmazan Would you be interested in doing this?

[jmuzsik]

Hi, I'll work on this, and I can do #3157 simultaneously.

Ought I use the exact text used in specified in #3157 or is there anything else that should be edited in this view?

Thanks!

[nlhkabu]

Great! thanks @jmuzsik! Yes, let's go with the exact text - thank you!

[di]

Fixed in #3313.