[maptips] restore wrapping of the long lines (fix #21388)

[alexbruy]

Description

Currently maptips shown as single line, no word-wrapping allowed and this does not work well with long text, it gets truncated and not visible. This restores previous behavior with enabled wrapping.

Fixes https://issues.qgis.org/issues/21388

Checklist

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[alexbruy]

@nirvn your feedback is more than welcome, as nowrap was added in one of the your commits

[nirvn]

@alexbruy , thanks for the heads up, I'll look at this tomorrow.

[nirvn]

@alexbruy , so looked into this early this morning. It doesn't break complex HTML maptips, so that's good.

The only downside I'm seeing is that the white space wrapping ends up wrapping most more-than-one-word maptips string; for e.g.:

I guess that's a small price to pay for being slightly more compatible out of the box. One can always use the HTML maptips to add a