Qt: Network-Traffic-Graph: make some distance between line and text

Text directly glued on the graph-line looks not so good.
Qt: Add support for missing scrollbar in peers table
Merge pull request #5218

236d96e Qt: Add support for missing scrollbar in peers table (Jonas Schnelli)
Merge pull request #5215

93a3f0e Qt: Network-Traffic-Graph: make some distance between line and text (Jonas Schnelli)