Make VcsLocation also implicitly shared
Summary:
While the mystery with the overloaded const/non-const
operator==(VcsLocation) yet has to be solved,
making the class itself implicitely shared seems an orthogonal thing.
Follow-up to 2965dae1af2618cfb7415ebfb0f02cb3e9cecf64 which did
the same for the other VCS data container classes.
Reviewers: KDevelop
Subscribers: aaronpuchert, mwolff, kdevelop-devel
Differential Revision: https://phabricator.kde.org/D8953