runtime(glimmer): add syntax support for glimmer files

runtime(glimmer): add syntax support for glimmer files

In commit cdf717283 ("patch 8.2.4424: ".gts" and ".gjs" files are not
recognized", 2022-02-19) support for the glimmer file types were added.

Problem:  Syntax hilighting suppoprt was missing.
Solution: Added a glimmer syntax file that will leverage the base
          syntaxs (javascript/typescript) and include handlebars syntax
          for .gjs/.gts files.

closes: #19569

Signed-off-by: Devin Weaver <suki@tritarget.org>
Signed-off-by: Christian Brabandt <cb@256bit.org>