try moving libucx dependency

dependencies.yaml

@@ -27,6 +27,13 @@ files:
       table: build-system
     includes:
       - build_python
+  py_rapids_build:
+    output: pyproject
+    pyproject_dir: .
+    extras:
+      table: tool.rapids-build-backend
+      key: requires
+    includes:
       - depends_on_ucx_build
   py_run:
     output: pyproject

pyproject.toml

@@ -16,7 +16,6 @@
 build-backend = "rapids_build_backend.build"
 requires = [
     "cython>=3.0.0",
-    "libucx==1.15.0",
     "rapids-build-backend>=0.3.0,<0.4.0dev0",
     "setuptools>=64.0.0",
 ] # This list was generated by `rapids-dependency-file-generator`. To make changes, edit dependencies.yaml and run `rapids-dependency-file-generator`.
@@ -119,6 +118,9 @@ commit-files = [
     "ucp/COMMIT_FILE"
 ]
 dependencies-file = "dependencies.yaml"
+requires = [
+    "libucx==1.15.0",
+] # This list was generated by `rapids-dependency-file-generator`. To make changes, edit dependencies.yaml and run `rapids-dependency-file-generator`.
 
 [tool.setuptools]
 license-files = ["LICENSE"]

setup.py

@@ -9,6 +9,9 @@
 import os
 from distutils.sysconfig import get_config_var, get_python_inc
 
+# TODO: delete this before merging. Just checking if this has to be available
+#       when setup.py is run.
+import libucx  # noqa: F401
 from Cython.Distutils.build_ext import new_build_ext
 from setuptools import setup
 from setuptools.extension import Extension
@@ -25,7 +28,7 @@ def _find_libucx_libs_and_headers():
     be compiled against those libucx-wheel-provided versions of the UCX libraries.
     """
     try:
-        import libucx
+        import libucx  # noqa: F811
     except ImportError:
         return [], []