[elpa] externals/llm updated (a3b4ba46f9 -> a5424e6637)

[ELPA Syncer]

elpasync pushed a change to branch externals/llm.

      from  a3b4ba46f9 Bump release to 0.5.1
       new  c93a836437 Fix mapconcat uses that only work in Emacs 29
       new  a5424e6637 Add support for Vertex model text-bison


Summary of changes:
 NEWS.org      |   3 +
 llm-ollama.el |   2 +-
 llm-openai.el |   2 +-
 llm-vertex.el | 223 ++++++++++++++++++++++++++++++++++++++--------------------
 4 files changed, 152 insertions(+), 78 deletions(-)