Chart titles and tooltip overlap charts in Monitoring on IE

[marius-dr]

Kibana version: 6.5.0

Browser version: IE 11

Original install method (e.g. download page, yum, from source, etc.): BC6

Describe the bug:
The chart titles and the tooltip button are overlapped by the charts on IE. The titles are still readable but it makes the tooltip harder to use as the area you can hover on is smaller.
This is a regression as it was OK on 6.4.x.

Screenshots (if relevant):
6.5.0

6.4.3

[elasticmachine]

Pinging @elastic/kibana-monitoring

[LeeDr]

I still see the problem on 6.6.0. Should be fixed, but I don't think it's a blocker for the next release.

[marius-dr]

Since we don't support IE any longer, we can close this.