[3.14] gh-142518: Move thread safety sections into a new page (GH-144716) (#145223)

- Create a new page for thread safety notes for built-in types
- Move thread safety notes for `list` into the new page
- Move thread safety notes for `dict` into the new page
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(cherry picked from commit 017ccd3bf420b79333f79f44a470c9c30a09aadc)

Co-authored-by: Lysandros Nikolaou <lisandrosnik@gmail.com>
Co-authored-by: Stan Ulbrych <89152624+StanFromIreland@users.noreply.github.com>