Temporarily disable gcc.download-ci-gcc

Because we renamed the CI component. We will have to re-enable it in a follow-up PR.

Author: Kobzol

src/ci/run.sh

@@ -188,7 +188,7 @@ else
   fi
 
   # Download GCC from CI on test builders
-  RUST_CONFIGURE_ARGS="$RUST_CONFIGURE_ARGS --set gcc.download-ci-gcc=true"
+  RUST_CONFIGURE_ARGS="$RUST_CONFIGURE_ARGS --set gcc.download-ci-gcc=false"
 
   # download-rustc seems to be broken on CI after the stage0 redesign
   # Disable it until these issues are debugged and resolved