Bump boto3 from 1.21.17 to 1.21.19 (#235)

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[//]: # (dependabot-end)

Bumps [boto3](https://github.com/boto/boto3) from 1.21.17 to 1.21.19.
<details>
<summary>Changelog</summary>
<p><em>Sourced from <a href="https://github.com/boto/boto3/blob/develop/CHANGELOG.rst">boto3's changelog</a>.</em></p>
<blockquote>
<h1>1.21.19</h1>
<ul>
<li>api-change:<code>kendra</code>: [<code>botocore</code>] Amazon Kendra now provides a data source connector for Slack. For more information, see <a href="https://docs.aws.amazon.com/kendra/latest/dg/data-source-slack.html">https://docs.aws.amazon.com/kendra/latest/dg/data-source-slack.html</a></li>
<li>api-change:<code>timestream-query</code>: [<code>botocore</code>] Amazon Timestream Scheduled Queries now support Timestamp datatype in a multi-measure record.</li>
<li>enhancement:Stubber: [<code>botocore</code>] Added support for modeled exception fields when adding errors to a client stub. Implements boto/boto3<code>[#3178](boto/boto3#3178) &lt;https://github.com/boto/botocore/issues/3178&gt;</code>__.</li>
<li>api-change:<code>elasticache</code>: [<code>botocore</code>] Doc only update for ElastiCache</li>
<li>api-change:<code>config</code>: [<code>botocore</code>] Add resourceType enums for AWS::ECR::PublicRepository and AWS::EC2::LaunchTemplate</li>
</ul>
<h1>1.21.18</h1>
<ul>
<li>api-change:<code>outposts</code>: [<code>botocore</code>] This release adds address filters for listSites</li>
<li>api-change:<code>lambda</code>: [<code>botocore</code>] Adds PrincipalOrgID support to AddPermission API. Customers can use it to manage permissions to lambda functions at AWS Organizations level.</li>
<li>api-change:<code>secretsmanager</code>: [<code>botocore</code>] Documentation updates for Secrets Manager.</li>
<li>api-change:<code>connect</code>: [<code>botocore</code>] This release adds support for enabling Rich Messaging when starting a new chat session via the StartChatContact API. Rich Messaging enables the following formatting options: bold, italics, hyperlinks, bulleted lists, and numbered lists.</li>
<li>api-change:<code>chime</code>: [<code>botocore</code>] Chime VoiceConnector Logging APIs will now support MediaMetricLogs. Also CreateMeetingDialOut now returns AccessDeniedException.</li>
</ul>
</blockquote>
</details>
<details>
<summary>Commits</summary>
<ul>
<li><a href="https://github.com/boto/boto3/commit/a657f829f9d07b2f2e6b5f5bf2aea48b64febae7"><code>a657f82</code></a> Merge branch 'release-1.21.19'</li>
<li><a href="https://github.com/boto/boto3/commit/8361ae704be9b8aac29e3e10774c929ff5780074"><code>8361ae7</code></a> Bumping version to 1.21.19</li>
<li><a href="https://github.com/boto/boto3/commit/fd92fcd8c5fa560341a746553a35244b92554037"><code>fd92fcd</code></a> Add changelog entries from botocore</li>
<li><a href="https://github.com/boto/boto3/commit/97069c53390424f4dbb5dfbd0fb50978c0fa650e"><code>97069c5</code></a> Merge branch 'release-1.21.18'</li>
<li><a href="https://github.com/boto/boto3/commit/b47fcdcdac0a32876c90251650fd9f6f82107e41"><code>b47fcdc</code></a> Merge branch 'release-1.21.18' into develop</li>
<li><a href="https://github.com/boto/boto3/commit/8c350e5231c3973de58fabe05f959c40acfa1f6d"><code>8c350e5</code></a> Bumping version to 1.21.18</li>
<li><a href="https://github.com/boto/boto3/commit/6b028241ec86dcdf5d6904f2e9f33230018c58b0"><code>6b02824</code></a> Add changelog entries from botocore</li>
<li><a href="https://github.com/boto/boto3/commit/da4cb3ed2ac9f133888e273dee1199ef99c47240"><code>da4cb3e</code></a> Merge branch 'release-1.21.17' into develop</li>
<li>See full diff in <a href="https://github.com/boto/boto3/compare/1.21.17...1.21.19">compare view</a></li>
</ul>
</details>
<br />


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