Change nightly_package_version to 2.9 (#9461)

Author: pgmoka

infra/tpu-pytorch-releases/artifacts_builds.tf

@@ -1,14 +1,14 @@
 ########## Begin section for release and nightly ########
-# Define common configuration parameters for 2.7 release and nightly
+# Define common configuration parameters for 2.8 release and nightly
 locals {
   tpu_python_versions = ["3.9", "3.10", "3.11", "3.12", "3.13"]
-  release_git_tag         = "v2.7.0-rc5"
-  release_package_version = "2.7.0-rc5"
-  release_pytorch_git_rev = "v2.7.0-rc10"
-  nightly_package_version = "2.8.0"
+  release_git_tag         = "v2.8.0-rc1"
+  release_package_version = "2.8.0-rc1"
+  release_pytorch_git_rev = "v2.8.0-rc1"
+  nightly_package_version = "2.9.0"
   cuda_versions = {
     "nightly": [],
-    "r2.7": ["12.1", "12.6"] # Note: PyTorch 2.7 release supports 11.8, 12.6, 12.8
+    "r2.8": ["12.1", "12.6"] # Note: PyTorch 2.8 release supports 11.8, 12.6, 12.8
   }
 
   # Built once a day from master