By default, when a snapshot version of an artifact is deployed to a repository, a timestamp is suffixed to it. To disable the addition of timestamp to the artifact, set the uniqueVersion parameter to false.
mvn deploy:deploy-file -Durl=file:///C:/m2-repo \
-DrepositoryId=some.id \
-Dfile=your-artifact-1.0.jar \
-DpomFile=your-pom.xml \
-DuniqueVersion=false