chore(deps): update dependency importlib-metadata to v5 (#257)

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This PR contains the following updates:

| Package | Change | Age | Adoption | Passing | Confidence |
|---|---|---|---|---|---|
| [importlib-metadata](https://togithub.com/python/importlib_metadata) | `==4.12.0` -> `==5.0.0` | [![age](https://badges.renovateapi.com/packages/pypi/importlib-metadata/5.0.0/age-slim)](https://docs.renovatebot.com/merge-confidence/) | [![adoption](https://badges.renovateapi.com/packages/pypi/importlib-metadata/5.0.0/adoption-slim)](https://docs.renovatebot.com/merge-confidence/) | [![passing](https://badges.renovateapi.com/packages/pypi/importlib-metadata/5.0.0/compatibility-slim/4.12.0)](https://docs.renovatebot.com/merge-confidence/) | [![confidence](https://badges.renovateapi.com/packages/pypi/importlib-metadata/5.0.0/confidence-slim/4.12.0)](https://docs.renovatebot.com/merge-confidence/) |

---

### Release Notes

<details>
<summary>python/importlib_metadata</summary>

### [`v5.0.0`](https://togithub.com/python/importlib_metadata/blob/HEAD/CHANGES.rst#v500)

[Compare Source](https://togithub.com/python/importlib_metadata/compare/v4.13.0...v5.0.0)

\======

-   [#&#8203;97](https://togithub.com/python/importlib_metadata/issues/97), [#&#8203;284](https://togithub.com/python/importlib_metadata/issues/284), [#&#8203;300](https://togithub.com/python/importlib_metadata/issues/300): Removed compatibility shims for deprecated entry
    point interfaces.

### [`v4.13.0`](https://togithub.com/python/importlib_metadata/blob/HEAD/CHANGES.rst#v4130)

[Compare Source](https://togithub.com/python/importlib_metadata/compare/v4.12.0...v4.13.0)

\=======

-   [#&#8203;396](https://togithub.com/python/importlib_metadata/issues/396): Added compatibility for `PathDistributions` originating
    from Python 3.8 and 3.9.

</details>

---

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Author: renovate-bot

.kokoro/requirements.txt

@@ -264,9 +264,9 @@ idna==3.4 \
     --hash=sha256:814f528e8dead7d329833b91c5faa87d60bf71824cd12a7530b5526063d02cb4 \
     --hash=sha256:90b77e79eaa3eba6de819a0c442c0b4ceefc341a7a2ab77d7562bf49f425c5c2
     # via requests
-importlib-metadata==4.12.0 \
-    --hash=sha256:637245b8bab2b6502fcbc752cc4b7a6f6243bb02b31c5c26156ad103d3d45670 \
-    --hash=sha256:7401a975809ea1fdc658c3aa4f78cc2195a0e019c5cbc4c06122884e9ae80c23
+importlib-metadata==5.0.0 \
+    --hash=sha256:da31db32b304314d044d3c12c79bd59e307889b287ad12ff387b3500835fc2ab \
+    --hash=sha256:ddb0e35065e8938f867ed4928d0ae5bf2a53b7773871bfe6bcc7e4fcdc7dea43
     # via
     #   -r requirements.in
     #   twine

requirements.txt

@@ -182,9 +182,9 @@ idna==3.4 \
     --hash=sha256:814f528e8dead7d329833b91c5faa87d60bf71824cd12a7530b5526063d02cb4 \
     --hash=sha256:90b77e79eaa3eba6de819a0c442c0b4ceefc341a7a2ab77d7562bf49f425c5c2
     # via requests
-importlib-metadata==4.12.0 \
-    --hash=sha256:637245b8bab2b6502fcbc752cc4b7a6f6243bb02b31c5c26156ad103d3d45670 \
-    --hash=sha256:7401a975809ea1fdc658c3aa4f78cc2195a0e019c5cbc4c06122884e9ae80c23
+importlib-metadata==5.0.0 \
+    --hash=sha256:da31db32b304314d044d3c12c79bd59e307889b287ad12ff387b3500835fc2ab \
+    --hash=sha256:ddb0e35065e8938f867ed4928d0ae5bf2a53b7773871bfe6bcc7e4fcdc7dea43
     # via alembic
 importlib-resources==5.9.0 \
     --hash=sha256:5481e97fb45af8dcf2f798952625591c58fe599d0735d86b10f54de086a61681 \