Fix crash in short link processor

[mrsdizzie]

Fixes #13819

[codecov-io]

Codecov Report

Merging #13839 (a239fb7) into master (c9effd5) will increase coverage by 0.09%.
The diff coverage is 36.36%.

@@            Coverage Diff             @@
##           master   #13839      +/-   ##
==========================================
+ Coverage   42.15%   42.25%   +0.09%     
==========================================
  Files         708      708              
  Lines       77167    77168       +1     
==========================================
+ Hits        32529    32604      +75     
+ Misses      39292    39197      -95     
- Partials     5346     5367      +21     

Impacted Files	Coverage Δ
modules/markup/html.go	78.83% <36.36%> (+0.03%)	⬆️
models/repo_mirror.go	2.38% <0.00%> (-11.91%)	⬇️
services/pull/check.go	48.90% <0.00%> (-3.65%)	⬇️
modules/cron/tasks_basic.go	87.35% <0.00%> (-3.45%)	⬇️
services/pull/temp_repo.go	26.59% <0.00%> (-3.20%)	⬇️
services/pull/patch.go	53.97% <0.00%> (-1.71%)	⬇️
modules/queue/unique_queue_disk_channel.go	53.84% <0.00%> (-1.54%)	⬇️
modules/queue/workerpool.go	58.77% <0.00%> (-1.23%)	⬇️
services/mirror/mirror.go	15.98% <0.00%> (-1.17%)	⬇️
services/pull/pull.go	40.68% <0.00%> (ø)
... and 12 more

---

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 c9effd5...a239fb7. Read the comment docs.