add pip to dagster-cloud.pex (#238)

Author: alangenfeld

scripts/release.py

@@ -123,7 +123,6 @@ def build_dagster_cloud_pex(
 
     info("Building generated/gha/dagster-cloud.pex")
     args = [
-        "pex",
         dagster_cloud_cli_pkg,
         dagster_pkg,
         dagster_dg_cli_pkg,
@@ -132,6 +131,7 @@ def build_dagster_cloud_pex(
         dagster_shared_pkg,
         "PyGithub",
         "pex>=2.1.132,<3",
+        "pip",
         "-o=dagster-cloud.pex",
         *complete_platform_args,
         "--pip-version=23.0",