[libcxx-commits] [libcxx] [libc++][CI] Improves updating Docker image. (PR #134497)

[Louis Dionne via libcxx-commits]

================
@@ -44,6 +44,10 @@
 ARG BASE_IMAGE
 FROM $BASE_IMAGE AS builder-base
 
+# Changing this file causes a rebuild of the image in a GitHub action.
+# The date uses the ISO format YYYY-MM-DD.
----------------
ldionne wrote:

```suggestion
# Changing this file causes a rebuild of the image in a GitHub action.
# However, it does not cause the CI runners to switch to that image automatically,
# that must be done by updating the SHA in the Github workflow file.
# The date uses the ISO format YYYY-MM-DD.
```

We can point to the documentation when we have some.

https://github.com/llvm/llvm-project/pull/134497