Update dependency com_github_grpc_grpc to v1.70.0

Author: renovate[bot]

bazel/zetasql_deps_step_2.bzl

@@ -275,9 +275,9 @@ py_library(
         if not native.existing_rule("com_github_grpc_grpc"):
             http_archive(
                 name = "com_github_grpc_grpc",
-                urls = ["https://github.com/grpc/grpc/archive/v1.43.2.tar.gz"],
-                sha256 = "b74ce7d26fe187970d1d8e2c06a5d3391122f7bc1fdce569aff5e435fb8fe780",
-                strip_prefix = "grpc-1.43.2",
+                urls = ["https://github.com/grpc/grpc/archive/v1.70.0.tar.gz"],
+                sha256 = "3c95034f6b23ce7d286e2e7b5f3f4f223720b8bb3f5a9662ff96b7013b2c3c26",
+                strip_prefix = "grpc-1.70.0",
             )
 
     if analyzer_deps: