TO-DROP: install libuserenv.a

When linking any Rust-generated library, GCC would complain about:

  undefined reference to `GetUserProfileDirectoryW'

Apparently there is _some_ closure that gets compiled in that requires
this function, and that in turn forces Git to link to libuserenv.

This is a new requirement, and therefore has not been made part of the
"minimal Git for Windows SDK".

In the near future, I intend to include it, but for now let's just
ensure that the file is added manually if it is missing.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>

Author: dscho

.github/workflows/main.yml

@@ -115,6 +115,14 @@ jobs:
     steps:
     - uses: actions/checkout@v4
     - uses: git-for-windows/setup-git-for-windows-sdk@v1
+    - name: ensure that libuserenv.a is present
+      shell: bash
+      run: |
+        cd /mingw64/lib && {
+          test -f libuserenv.a ||
+          /c/Program\ Files/Git/mingw64/bin/curl -Lo libuserenv.a \
+            https://github.com/git-for-windows/git-sdk-64/raw/HEAD/mingw64/lib/libuserenv.a
+        }
     - name: build
       shell: bash
       env: