Fixed using Bash in shell command

- without this, the syntax is not recognised because we use `sh`

tools/BinaryBuilder.Dockerfile

@@ -5,7 +5,7 @@ FROM node:$NODE_VERSION-$VARIANT
 
 ARG VARIANT
 
-RUN if [[ "$VARIANT" =~ alpine* ]] ; then apk add build-base python3 --update-cache ; fi
+RUN if case $VARIANT in "alpine"*) true;; *) false;; esac; then apk add build-base python3 --update-cache ; fi
 
 WORKDIR /usr/src/build
 
@@ -22,7 +22,7 @@ ENV CXXFLAGS="${CXXFLAGS:-} -include ../src/gcc-preinclude.h"
 RUN npx node-pre-gyp configure
 RUN npx node-pre-gyp build
 
-RUN if [[ ! "$VARIANT" =~ alpine* ]] ; then ldd lib/binding/*/node_sqlite3.node; nm lib/binding/*/node_sqlite3.node | grep "GLIBC_" | c++filt || true ; fi
+RUN if case $VARIANT in "alpine"*) false;; *) true;; esac; then ldd lib/binding/*/node_sqlite3.node; nm lib/binding/*/node_sqlite3.node | grep \"GLIBC_\" | c++filt || true ; fi
 
 RUN npm run test
 RUN npx node-pre-gyp package