chore(deps): update dependency pypandoc to v1.7.2 (#1111)

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This PR contains the following updates:

| Package | Change | Age | Adoption | Passing | Confidence |
|---|---|---|---|---|---|
| [pypandoc](https://togithub.com/bebraw/pypandoc) | `==1.6.4` -> `==1.7.2` | [![age](https://badges.renovateapi.com/packages/pypi/pypandoc/1.7.2/age-slim)](https://docs.renovatebot.com/merge-confidence/) | [![adoption](https://badges.renovateapi.com/packages/pypi/pypandoc/1.7.2/adoption-slim)](https://docs.renovatebot.com/merge-confidence/) | [![passing](https://badges.renovateapi.com/packages/pypi/pypandoc/1.7.2/compatibility-slim/1.6.4)](https://docs.renovatebot.com/merge-confidence/) | [![confidence](https://badges.renovateapi.com/packages/pypi/pypandoc/1.7.2/confidence-slim/1.6.4)](https://docs.renovatebot.com/merge-confidence/) |

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### Release Notes

<details>
<summary>bebraw/pypandoc</summary>

### [`v1.7.0`](https://togithub.com/bebraw/pypandoc/releases/v1.7.0)

[Compare Source](https://togithub.com/bebraw/pypandoc/compare/v1.6.4...v1.7.0)

This release of PyPandoc enables the new sandbox mode of pandoc >= 2.…
…15 by default. This can be toggled and has no effect on pandoc versions < 2.15. In addition this release also adds an option to verify from and to formats before converting, reducing the calls to pandoc.

Two new utility functions has also been added (ensure_pandoc_minimal_version and ensure_pandoc_maximal_version), to check the major and minor version of the pandoc currently being used.
In addition, the old convert() function, has been set to be removed in the next major release of PyPandoc (1.8)
Other than that, a few bug fixes here and there.

-   [#&#8203;245](https://togithub.com/bebraw/pypandoc/issues/245)
-   [#&#8203;244](https://togithub.com/bebraw/pypandoc/issues/244)
-   [#&#8203;231](https://togithub.com/bebraw/pypandoc/issues/231)
-   [#&#8203;240](https://togithub.com/bebraw/pypandoc/issues/240)
-   [#&#8203;241](https://togithub.com/bebraw/pypandoc/issues/241)
-   [#&#8203;238](https://togithub.com/bebraw/pypandoc/issues/238)
-   [#&#8203;237](https://togithub.com/bebraw/pypandoc/issues/237)
-   [#&#8203;235](https://togithub.com/bebraw/pypandoc/issues/235)
-   [#&#8203;225](https://togithub.com/bebraw/pypandoc/issues/225)
-   [#&#8203;226](https://togithub.com/bebraw/pypandoc/issues/226)
-   [#&#8203;227](https://togithub.com/bebraw/pypandoc/issues/227)
-   [#&#8203;229](https://togithub.com/bebraw/pypandoc/issues/229)

</details>

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requirements.txt

@@ -4,6 +4,6 @@ googleapis-common-protos==1.54.0
 jinja2==3.0.3
 MarkupSafe==2.0.1
 protobuf==3.19.3
-pypandoc==1.6.4
+pypandoc==1.7.2
 PyYAML==6.0
 dataclasses==0.6 # TODO(busunkim) remove when 3.6 support is dropped