Fix logo appearance in header on mobile view

[melissaing]

With the addition of another button in the header, the PatternFly logo will shrink or disappear in mobile screen resolutions.

Galaxy S10/S10+ Android 11 (360 x 760):

iPhone 12/13 + Pro iOS 14.6 (390 x 844)

Also seen on smaller and non-standard screen resolutions even without another button:
Typical size vs. 342 x 896

Edit:
Also seen in the header demo.

[rebeccaalpert]

Similarly, iPhone SE, Galaxy Z fold 5 and S8+ scrolls (due to overflow when there are a lot of header items):