Describe the issue
In Ruby, single quote and double quote strings work differently:

In addition to disabling interpolation [(#{} syntax)], single-quoted strings also disable all escape sequences except for the single-quote (\') and backslash (\\).

https://docs.ruby-lang.org/en/3.1/syntax/literals_rdoc.html#label-Strings

But in ruby.js, they are implemented identically

which leads it to incorrectly highlight #{} substitutions in single quoted strings which actually have no effect, they are just literal #{} characters (in the "github" theme):

instead of highlighting it as a string, like it does if we remove the #:

Which language seems to have the issue?
Ruby

Are you using highlight or highlightAuto?
N/A

Expected behavior
Single and double quoted strings should have separate highlighting rules for Ruby.

Additional context
https://docs.ruby-lang.org/en/3.1/syntax/literals_rdoc.html#label-Strings

Unrelated, but for double quoted strings, that page also lists a couple interpolation syntax shorthands that are not implemented in the highlight.js grammar:

You can also use #@foo, #@@foo and #$foo as a shorthand for, respectively, #{ @foo }, #{ @@foo } and #{ $foo }.