Merge default and system webhooks under one menu

[lafriks]

Before:

After:

[lunny]

@lafriks Please update

[lafriks]

@lunny done :)

[codecov-io]

Codecov Report

Merging #14244 (d0a71be) into master (84b147c) will decrease coverage by 0.00%.
The diff coverage is 24.56%.

@@            Coverage Diff             @@
##           master   #14244      +/-   ##
==========================================
- Coverage   41.85%   41.85%   -0.01%     
==========================================
  Files         744      744              
  Lines       79639    79638       -1     
==========================================
- Hits        33335    33331       -4     
  Misses      40816    40816              
- Partials     5488     5491       +3     

Impacted Files	Coverage Δ
models/webhook.go	71.20% <0.00%> (+2.13%)	⬆️
routers/admin/hooks.go	0.00% <0.00%> (ø)
routers/org/setting.go	0.00% <0.00%> (ø)
routers/repo/webhook.go	1.16% <6.25%> (+0.12%)	⬆️
routers/routes/macaron.go	93.24% <100.00%> (+0.01%)	⬆️
modules/util/timer.go	42.85% <0.00%> (-42.86%)	⬇️
modules/queue/unique_queue_disk_channel.go	53.84% <0.00%> (-1.54%)	⬇️
modules/queue/workerpool.go	57.95% <0.00%> (-0.82%)	⬇️

---

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 84b147c...d0a71be. Read the comment docs.

[lafriks]

🚀