Fixing docs build problem

[isaacgsmith]

Description

Fixes the broken documentation build.

Motivation and context

After the merge of #1562 the documentation did not build properly.

How has this been tested?

• Testing pipeline.
• Other.
  Successfully built docs can be found here.

Type of change

• Bug fix.
• New feature.
• Breaking change.
• None of the above.

Checklist

• My change requires a change to the documentation.
  • I have updated the documentation accordingly.
  • (optional) I have built the documentation on my fork following the instructions.
• I have assigned and requested two reviewers for this pull request.

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[codecov]

Codecov Report

Merging #1569 (b348a64) into master (6e31dc4) will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master    #1569   +/-   ##
=======================================
  Coverage   67.05%   67.05%           
=======================================
  Files          73       73           
  Lines        6144     6144           
=======================================
  Hits         4120     4120           
  Misses       2024     2024           

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