Update Sourcegraph Docker insiders images

[sourcegraph-bot]

This PR contains the following updates:

Package	Update	Change
index.docker.io/sourcegraph/cadvisor	digest	9da4e18 -> 636b94e
index.docker.io/sourcegraph/frontend	digest	6a6215e -> df6f884
index.docker.io/sourcegraph/github-proxy	digest	e5cd297 -> 38c81c9
index.docker.io/sourcegraph/gitserver	digest	3d8b7bf -> ba9af29
index.docker.io/sourcegraph/grafana	digest	7026614 -> a237fa2
index.docker.io/sourcegraph/jaeger-agent	digest	c60c358 -> 5ae05f5
index.docker.io/sourcegraph/jaeger-all-in-one	digest	17b7ab2 -> 2887a56
index.docker.io/sourcegraph/precise-code-intel-worker	digest	9b25342 -> c8db3bb
index.docker.io/sourcegraph/prometheus	digest	1f978b5 -> fbb968a
index.docker.io/sourcegraph/query-runner	digest	55347d7 -> 2d520e0
index.docker.io/sourcegraph/repo-updater	digest	540141a -> 0cfd808
index.docker.io/sourcegraph/searcher	digest	0019c6d -> de4f31a
index.docker.io/sourcegraph/symbols	digest	f63db70 -> 54a6305

Source: https://github.com/sourcegraph/sourcegraph/pull/18122

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