Use ubuntu 24.04 for PostCommit TransformService Direct

.github/workflows/beam_PostCommit_TransformService_Direct.yml

diff --git a/.github/workflows/beam_PostCommit_TransformService_Direct.yml b/.github/workflows/beam_PostCommit_TransformService_Direct.yml
index bd9e449..0c2a343 100644
--- a/.github/workflows/beam_PostCommit_TransformService_Direct.yml
+++ b/.github/workflows/beam_PostCommit_TransformService_Direct.yml
@@ -55,7 +55,7 @@
       github.event_name == 'pull_request_target' ||
       (github.event_name == 'schedule' && github.repository == 'apache/beam') ||
       github.event.comment.body == 'Run TransformService_Direct PostCommit'
-    runs-on: [self-hosted, ubuntu-20.04, main]
+    runs-on: [self-hosted, ubuntu-24.04, main]
     timeout-minutes: 120
     name: ${{ matrix.job_name }} (${{ matrix.job_phrase }} ${{ matrix.python_version }})
     strategy:
@@ -99,4 +99,4 @@
           commit: '${{ env.prsha || env.GITHUB_SHA }}'
           comment_mode: ${{ github.event_name == 'issue_comment'  && 'always' || 'off' }}
           files: '**/pytest*.xml'
-          large_files: true
\ No newline at end of file
+          large_files: true