Clone repositories with --depth 1 (#24)

Author: RA80533

Dockerfile

@@ -63,9 +63,9 @@ RUN mkdir -p ${CODEQL_HOME} \
     /opt/codeql
 
 # get the latest codeql queries and record the HEAD
-RUN git clone https://github.com/github/codeql ${CODEQL_HOME}/codeql-repo && \
+RUN git clone --depth 1 https://github.com/github/codeql ${CODEQL_HOME}/codeql-repo && \
     git --git-dir ${CODEQL_HOME}/codeql-repo/.git log --pretty=reference -1 > /opt/codeql/codeql-repo-last-commit
-RUN git clone https://github.com/github/codeql-go ${CODEQL_HOME}/codeql-go-repo && \
+RUN git clone --depth 1 https://github.com/github/codeql-go ${CODEQL_HOME}/codeql-go-repo && \
     git --git-dir ${CODEQL_HOME}/codeql-go-repo/.git log --pretty=reference -1 > /opt/codeql/codeql-go-repo-last-commit
 
 RUN CODEQL_VERSION=$(cat /tmp/codeql_version) && \