Pin llvm-mingw to non-broken version

Author: BtbN

images/base-winarm64/Dockerfile

@@ -2,7 +2,7 @@ ARG GH_REPO=ghcr.io/btbn/ffmpeg-builds
 FROM $GH_REPO/base:latest
 
 RUN \
-    git clone --filter=blob:none https://github.com/mstorsjo/llvm-mingw /llvm-mingw && cd /llvm-mingw && \
+    git-mini-clone https://github.com/mstorsjo/llvm-mingw.git 747a6cd27a7e3e313eb6bc1433aa1221044df8ca /llvm-mingw && cd /llvm-mingw && \
     ./build-all.sh --disable-lldb --disable-lldb-mi /opt/llvm-mingw && \
     cd / && \
     rm -rf llvm-mingw