[LyX/master] Disable direct insertion of multiple spaces in mathed text

[Richard Kimberly Heck]

On 2/4/21 3:20 PM, Enrico Forestieri wrote:
> commit 8202e4e571b90b3b87918437d6346bbf1cbfc6aa
> Author: Enrico Forestieri <forenr at lyx.org>
> Date:   Thu Feb 4 21:20:45 2021 +0100
>
>      Disable direct insertion of multiple spaces in mathed text
>      
>      Fixes #1311

An old one!

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