Update python:3.6-slim Docker digest to a37682 (#941)
Update python:3.6-slim Docker digest to a37682 (#941)

<p>This Pull Request updates Docker base image <code>python:3.6-slim</code> to the latest digest (<code>sha256:a3768242f4ab7fa41113a36a714c63c65af11d281ae05faf098130a1c5d92889</code>). For details on Renovate's Docker support, please visit <a href="https://renovatebot.com/docs/docker">https://renovatebot.com/docs/docker</a></p>
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<p>This PR has been generated by <a href="https://renovatebot.com">Renovate Bot</a>.</p>
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