Change drone token name to let users know to use oauth2

[techknowlogick]

This changes the name of the drone token so that basic auth is still allowed (but points user in direction of using oauth2)

[codecov-io]

Codecov Report

Merging #6912 into master will decrease coverage by <.01%.
The diff coverage is 40%.

@@            Coverage Diff             @@
##           master    #6912      +/-   ##
==========================================
- Coverage   41.42%   41.42%   -0.01%     
==========================================
  Files         440      440              
  Lines       59738    59744       +6     
==========================================
- Hits        24749    24747       -2     
- Misses      31752    31760       +8     
  Partials     3237     3237

Impacted Files	Coverage Δ
routers/api/v1/user/app.go	60.57% <40%> (-2.69%)	⬇️
models/unit.go	62.16% <0%> (-5.41%)	⬇️
routers/repo/view.go	42.02% <0%> (-1.02%)	⬇️
modules/log/event.go	65.98% <0%> (+1.52%)	⬆️

---

Continue to review full report at Codecov.

Legend - Click here to learn more
Δ = absolute <relative> (impact), ø = not affected, ? = missing data
Powered by Codecov. Last update 13583a6...0fdd44c. Read the comment docs.

[zeripath]

Lgtm but I know nothing about Drone

[lafriks]

Is this really only option?

[techknowlogick]

What users should be doing is using OAuth2, however some don't. So this will resolve the broken connection when they try to use basic auth with drone, however it'll let them know they should be using OAuth2.

Basic auth connection with drone is already not working due with users that use 2FA, and so if users want to be secure they should be using OAuth2. And as we've seen from recent attacks against SCM providers, 2FA is essentially mandatory if you want to keep your code safe.

I see this PR as temporary, and once 1.9.0 is final we can put in blog post that users should switch to OAuth2 for Drone, and then we can remove it for 1.10.0

[lafriks]

But wouldn't generate lots of tokens this way?

[techknowlogick]

@lafriks yes, it would. This encourages users to switch to OAuth2 (basic auth for Gitea will be removed in next release of Drone)