Fix typo in dockerfile

mapserver/Dockerfile

@@ -23,7 +23,7 @@ RUN mkdir -p /build_deps && cd /build_deps \
   && mkdir -p build && cd build \
   && cmake .. -DWITH_PROTOBUFC=OFF -DWITH_POSTGIS=OFF \
   && make -j$(nproc) \
-  && make install
+  && make install \
   && cd && rm -rf /build_deps
 
 # apache