Cleanup: use '#' prefix for issues instead of 'T'

Match the convention from Gitea instead of Phabricator's T for tasks.

source/blender/gpu/intern/gpu_codegen.cc

@@ -369,7 +369,7 @@ void GPUCodegen::generate_resources()
 {
   GPUCodegenCreateInfo &info = *create_info;
 
-  /* Ref. T98190: Defines are optimizations for old compilers.
+  /* Ref. #98190: Defines are optimizations for old compilers.
    * Might become unnecessary with EEVEE-Next. */
   if (GPU_material_flag_get(&mat, GPU_MATFLAG_PRINCIPLED_CLEARCOAT)) {
     info.define("PRINCIPLED_CLEARCOAT");