v20260120.002357: Bump actions/download-artifact from 4 to 6 (#30)

diff -rNU0 a/msys2-clangarm64-mingw-w64@r688.packages.txt b/msys2-clangarm64-mingw-w64@r688.packages.txt
--- a/msys2-clangarm64-mingw-w64@r688.packages.txt	2026-01-20 00:20:38.403283620 +0000
+++ b/msys2-clangarm64-mingw-w64@r688.packages.txt	2026-01-20 00:20:39.994274511 +0000
@@ -94,3 +94,3 @@
-mingw-w64-clang-aarch64-clang 21.1.8-2
-mingw-w64-clang-aarch64-clang-libs 21.1.8-2
-mingw-w64-clang-aarch64-compiler-rt 21.1.8-2
+mingw-w64-clang-aarch64-clang 21.1.8-3
+mingw-w64-clang-aarch64-clang-libs 21.1.8-3
+mingw-w64-clang-aarch64-compiler-rt 21.1.8-3
@@ -99 +99 @@
-mingw-w64-clang-aarch64-gcc-compat 21.1.8-2
+mingw-w64-clang-aarch64-gcc-compat 21.1.8-3
@@ -118,3 +118,3 @@
-mingw-w64-clang-aarch64-lld 21.1.8-2
-mingw-w64-clang-aarch64-llvm-libs 21.1.8-2
-mingw-w64-clang-aarch64-llvm-tools 21.1.8-2
+mingw-w64-clang-aarch64-lld 21.1.8-3
+mingw-w64-clang-aarch64-llvm-libs 21.1.8-3
+mingw-w64-clang-aarch64-llvm-tools 21.1.8-3
diff -rNU0 a/msys2-clangarm64.packages.txt b/msys2-clangarm64.packages.txt
--- a/msys2-clangarm64.packages.txt	2026-01-20 00:20:38.701281914 +0000
+++ b/msys2-clangarm64.packages.txt	2026-01-20 00:20:40.113273829 +0000
@@ -94,3 +94,3 @@
-mingw-w64-clang-aarch64-clang 21.1.8-2
-mingw-w64-clang-aarch64-clang-libs 21.1.8-2
-mingw-w64-clang-aarch64-compiler-rt 21.1.8-2
+mingw-w64-clang-aarch64-clang 21.1.8-3
+mingw-w64-clang-aarch64-clang-libs 21.1.8-3
+mingw-w64-clang-aarch64-compiler-rt 21.1.8-3
@@ -99 +99 @@
-mingw-w64-clang-aarch64-gcc-compat 21.1.8-2
+mingw-w64-clang-aarch64-gcc-compat 21.1.8-3
@@ -118,3 +118,3 @@
-mingw-w64-clang-aarch64-lld 21.1.8-2
-mingw-w64-clang-aarch64-llvm-libs 21.1.8-2
-mingw-w64-clang-aarch64-llvm-tools 21.1.8-2
+mingw-w64-clang-aarch64-lld 21.1.8-3
+mingw-w64-clang-aarch64-llvm-libs 21.1.8-3
+mingw-w64-clang-aarch64-llvm-tools 21.1.8-3