ci: retrigger E2E AutoTest against @vscjava/vscode-autotest@0.7.8

The 0.7.7 release did not actually honor skipLlmVerify because
planParser dropped the field on deserialize. 0.7.8 contains the
parser fix; this empty commit restarts CI so the matrix installs
the correct version.

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

Author: wenytang-ms