Pin specific commit for all Git clones

This helps ensure that container builds are reproducible if thirdparty
repositories change.

Dockerfile.ios

@@ -5,6 +5,7 @@ RUN dnf -y install --setopt=install_weak_deps=False \
     dnf clean all && \
     git clone https://github.com/tpoechtrager/cctools-port.git && \
     cd /root/cctools-port && \
+    git checkout 8239a5211bcf07d6b9d359782e1a889ec1d7cce5 && \
     sed -i 's#./autogen.sh#libtoolize -c -i --force\n./autogen.sh#' usage_examples/ios_toolchain/build.sh && \
     usage_examples/ios_toolchain/build.sh /root/files/iPhoneOS12.4.sdk.tar.xz arm64 && \
     mkdir -p /root/ioscross/arm64 && \

Dockerfile.javascript

@@ -7,6 +7,7 @@ RUN dnf -y install --setopt=install_weak_deps=False \
     dnf clean all && \
     git clone https://github.com/emscripten-core/emsdk && \
     cd emsdk && \
+    git checkout a5082b232617c762cb65832429f896c838df2483 && \
     ./emsdk install 1.38.47-upstream && \
     ./emsdk activate 1.38.47-upstream && \
     echo "source /root/emsdk/emsdk_env.sh" >> /root/.bashrc

Dockerfile.xcode

@@ -5,11 +5,13 @@ RUN dnf -y install --setopt=install_weak_deps=False \
     dnf clean all && \
     git clone https://github.com/mackyle/xar.git && \
     cd xar/xar && \
+    git checkout 66d451dab1ef859dd0c83995f2379335d35e53c9 && \
     ./autogen.sh --prefix=/usr && \
     make -j && make install && \
     cd /root && \
     git clone https://github.com/NiklasRosenstein/pbzx && \
     cd pbzx && \
+    git checkout 2a4d7c3300c826d918def713a24d25c237c8ed53 && \
     clang -O3 -llzma -lxar -I /usr/local/include pbzx.c -o pbzx
 
 CMD mkdir -p /root/xcode && \