replace ~ with . for marking up sections

[qleroy]

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This PR restores the preview feature for ./BREEZE.rst.
I described the issue here #33368 .
The change replaces the tilde ~ character for marking section with -.

[boring-cyborg]

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[potiuk]

Right. but better fix will be to replace it with `........................" (dots.) - the problem is that the TOC level is now inconsistent with some previous TOC levels (SBOM) (and ..... will bring the consistency back).

[boring-cyborg]

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