Speed up jsDeserialize (again; see 74749311): don't copy at all but overwrite source string

1 job for javascript-interface-enhancements-for-svg-library in 1 minute and 4 seconds (queued for 2 seconds)
Status Job ID Name Coverage
  Test
failed #55734
test

00:01:04

 
Name Stage Failure
failed
test Test
Analyzing 'iTasks.Internal.Tonic.Images'. 
[iTasks.Internal.Tonic.Images.icl,]: no abc file
Compiling 'iTasks.Internal.Tonic.Images'.
Error [iTasks.Internal.Tonic.Images.icl,29,import]: OnNClickAttr not exported as a type by module Graphics.Scalable.Image
Error [iTasks.Internal.Tonic.Images.icl,21,import]: tuneImage not exported as a instance by module Graphics.Scalable.Image
Finished making.
xargs: sh: exited with status 255; aborting
'/opt/clean/etc/IDEEnvs.bak2' -> '/opt/clean/etc/IDEEnvs'
ERROR: Job failed: exit code 1