Convert fringe bitmaps to vectors on NS port

Unfortunately *step doesn't support masks for bitmap images so
changing the colors of fringe bitmaps is awkward.  We can work around
this by converting the bitmap into an NSBezierPath and drawing it in
the required color.

* src/nsterm.m (ns_define_fringe_bitmap):
(ns_destroy_fringe_bitmap): New functions
(ns_draw_fringe_bitmap): Display the NSBezierPath.
* src/nsimage.m
([EmacsImage initFromXBM:width:height:fg:bg:reverseBytes:]): Remove
variable that's there to allow us to easily modify the XBM colors.
([EmacsImage setXBMColor:]): Remove method.
8 jobs for master in 12 seconds (queued for 4 seconds)
Status Job ID Name Coverage
  Prep Images
failed #24227
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build-image-filenotify-gio
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build-image-gnustep
 
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test-filenotify-gio
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test-gnustep
 
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test-all-inotify
 
Name Stage Failure
failed
prep-image-base Prep Images There has been a runner system failure, please try again
$ git config --global http.proxy $HTTP_PROXY; git config --global https.proxy $HTTPS_PROXY
Fetching changes with git depth set to 50...
Reinitialized existing Git repository in /builds/emacs/emacs/.git/
From https://emba.gnu.org/emacs/emacs
* [new ref] d2d3fc39295953b4db5bdd7a21d513a87d3d00f0 -> refs/pipelines/11610
Checking out d2d3fc39 as master...

Skipping Git submodules setup
ERROR: Job failed (system failure): Error response from daemon: Conflict. The container name "/runner-2oEDrUT7-project-1-concurrent-1-build-4" is already in use by container "f46df44a43bee1f61a6ede2eac732a4e06eaa2094659f7ea23718f093d67bcc6". You have to remove (or rename) that container to be able to reuse that name. (executor_docker.go:726:0s)