build: extract temporal_capi crate directory name into gyp variable

This is a no-op for current builds, but will allow the crate updater in
node-core-utils to update the include path with the new crate location,
as the crate directory names will include a version string.

Signed-off-by: Renegade334 <contact.9a5d6388@renegade334.me.uk>
PR-URL: #64482
Reviewed-By: Antoine du Hamel <duhamelantoine1995@gmail.com>
Reviewed-By: Michaël Zasso <targos@protonmail.com>
Reviewed-By: Chengzhong Wu <legendecas@gmail.com>

Author: Renegade334

deps/crates/crates.gyp

@@ -2,6 +2,7 @@
   'variables': {
     'cargo%': 'cargo',
     'cargo_vendor_dir': './vendor',
+    'temporal_capi_dir': 'temporal_capi',
     'cargo_rust_target%': '',
   },
   'conditions': [
@@ -120,7 +121,7 @@
       ],
       'direct_dependent_settings': {
         'include_dirs': [
-          '<(cargo_vendor_dir)/temporal_capi/bindings/cpp',
+          '<(cargo_vendor_dir)/<(temporal_capi_dir)/bindings/cpp',
         ],
       },
     },