go: Support raw string subtest names (#34636)

Currently, we're not able to run Go sub-tests that have a raw string
(e.g. we're using multi-line names a lot) via the UI. I added the
changes that are needed, plus a handful of tests to cover the basics.

Quick comparison:

Before:
<img width="901" height="370" alt="before"
src="https://github.com/user-attachments/assets/4e5cadeb-9a0c-49e2-b976-2223e1010f85"
/>



After:
<img width="901" height="505" alt="after"
src="https://github.com/user-attachments/assets/994fc69b-f720-488c-a14b-853a3ca2f53c"
/>


Release Notes:

- Added support for Go subtest runner with raw string names

crates/languages/src/go/runnables.scm

@@ -38,7 +38,10 @@
       arguments: (
         argument_list
         .
-        (interpreted_string_literal) @_subtest_name
+        [
+          (interpreted_string_literal)
+          (raw_string_literal)
+        ] @_subtest_name
         .
         (func_literal
           parameters: (