Its not correct way of doing this , you should not put any jar manually in WEB-INF/lib folder.
And if that jar is not available in MAVEN CENTRAL REPO , then you can download it and install it in your NEXUS CENTRAL REPO (if you have any) otherwise put that jar in your local maven repository and add it as a dependency in your pom file. If you don't want to include that jar in your WEB-INF/lib then change the scope to provided otherwise leave it as default i.e compile.
During build time MAVEN will look for that particular jar in your local repo first , and if it don't find it there then it try to download from Centra Repo.
Once it is available in your local repo , your build won't break.