Update the tar command to use additional tar options

Co-authored-by: Fabian Fett <[email protected]>

Author: shahmishal

nightly-main/amazonlinux/2/buildx/Dockerfile

@@ -61,7 +61,7 @@ RUN set -e; \
     && curl -fSsL https://swift.org/keys/all-keys.asc | gpg --import -  \
     && gpg --batch --verify latest_toolchain.tar.gz.sig latest_toolchain.tar.gz \
     # - Unpack the toolchain, set libs permissions, and clean up.
-    && tar -xzf latest_toolchain.tar.gz --directory / --strip-components=1 \
+    && tar -xzf latest_toolchain.tar.gz --directory / ${ADDITIONAL_TAR_OPTIONS} \
     && chmod -R o+r /usr/lib/swift \
     && rm -rf "$GNUPGHOME" latest_toolchain.tar.gz.sig latest_toolchain.tar.gz \