fix: return cookie value in getCookieValueFromString instead of null

Also trim cookie names correctly.
6 jobs for topic/default/fix-csrf in 3 minutes and 51 seconds (queued for 25 seconds)
Status Job ID Name Coverage
  Deps
passed Deps #389798

00:01:47

passed TestServerImage #389799

00:01:21

 
  Test
passed CanBuild #389802

00:00:47

passed Format #389801

00:00:33

passed Lint #389800

00:00:43

passed Tests #389803

00:01:04