Versioning improvements (#768)

Co-authored-by: ReenigneArcher <42013603+ReenigneArcher@users.noreply.github.com>

docker/archlinux.dockerfile

@@ -22,11 +22,16 @@ RUN useradd -m builder && \
 
 FROM sunshine-base as sunshine-build
 
+ARG BRANCH
 ARG BUILD_VERSION
 ARG COMMIT
 ARG CLONE_URL
 # note: BUILD_VERSION may be blank
 
+ENV BRANCH=${BRANCH}
+ENV BUILD_VERSION=${BUILD_VERSION}
+ENV COMMIT=${COMMIT}
+
 SHELL ["/bin/bash", "-o", "pipefail", "-c"]
 # install dependencies
 # cuda, libcap, and libdrm are optional dependencies for PKGBUILD
@@ -37,6 +42,7 @@ pacman -Syu --noconfirm \
   base-devel \
   cmake \
   cuda \
+  git \
   libcap \
   libdrm \
   namcap