Output from failed platform_triplet.c compilation is not logged

Bug report

Bug description:

In #117886, building platform_triplet.c was failing, but the only output in config.log was:

configure:6892: checking for the platform triplet based on compiler characteristics
configure:6900: result: none

At least in the case of failure, the compile command and output should be logged.

CPython versions tested on:

3.13

Operating systems tested on:

macOS

Linked PRs

• gh-134905

從報告中描述的 platform_triplet.c 編譯和 configure 進入點開始。將失敗建置的命令和輸出與目前寫入 config.log 的內容進行比較。完成的標準是：失敗的編譯會記錄編譯命令及其輸出；查看已連結的 PR gh-134905，了解現有工作。