[MRG] Partial fix for doc build issues with notebooks

[luizirber]

Seems like something changed with myst-parser 0.14.0 that broke our notebooks. At first it seemed to be missing tags in the metadata field of each cell in the notebook, but when I fixed that it triggered errors about missing widgets fields, and so... I'm pinning myst-parser to 0.13.7 for now.

[codecov]

Codecov Report

Merging #1516 (5b1b246) into latest (f60c44d) will increase coverage by 5.03%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##           latest    #1516      +/-   ##
==========================================
+ Coverage   90.26%   95.29%   +5.03%     
==========================================
  Files         126       99      -27     
  Lines       21099    17399    -3700     
  Branches     1585     1585              
==========================================
- Hits        19045    16581    -2464     
+ Misses       1827      591    -1236     
  Partials      227      227              

Flag	Coverage Δ
python	95.29% <ø> (ø)
rust	?

Flags with carried forward coverage won't be shown. Click here to find out more.

Impacted Files	Coverage Δ
src/core/src/signature.rs
src/core/src/index/linear.rs
src/core/src/sketch/hyperloglog/mod.rs
src/core/src/index/bigsi.rs
src/core/src/sketch/hyperloglog/estimators.rs
src/core/src/ffi/signature.rs
src/core/tests/minhash.rs
src/core/src/index/storage.rs
src/core/src/wasm.rs
src/core/src/sketch/minhash.rs
... and 17 more

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[luizirber]

Ready for review and merge @ctb @bluegenes

[bluegenes]

lgtm!