Update Sourcegraph Docker insiders images

[sourcegraph-bot]

This PR contains the following updates:

Package	Update	Change
index.docker.io/sourcegraph/cadvisor	digest	dd33b24 -> f0351e4
index.docker.io/sourcegraph/frontend	digest	c28ae1f -> 869563f
index.docker.io/sourcegraph/github-proxy	digest	a4048e5 -> 8786fbd
index.docker.io/sourcegraph/gitserver	digest	c461f3a -> c18fc7a
index.docker.io/sourcegraph/grafana	digest	b7b9b58 -> 7cc43b5
index.docker.io/sourcegraph/indexed-searcher	digest	1e5040b -> 7cd80af
index.docker.io/sourcegraph/jaeger-agent	digest	702048d -> 86b1ec1
index.docker.io/sourcegraph/jaeger-all-in-one	digest	beb14a9 -> 3703b98
index.docker.io/sourcegraph/precise-code-intel-worker	digest	074b2a8 -> 2d44a5d
index.docker.io/sourcegraph/prometheus	digest	741ad88 -> f859876
index.docker.io/sourcegraph/query-runner	digest	c4468c1 -> a6d6961
index.docker.io/sourcegraph/repo-updater	digest	5c0363e -> 376b688
index.docker.io/sourcegraph/search-indexer	digest	fbcf55d -> 42081da
index.docker.io/sourcegraph/searcher	digest	3fa1f2e -> c8c9a2e
index.docker.io/sourcegraph/symbols	digest	88acaa9 -> da68ca3
index.docker.io/sourcegraph/syntax-highlighter	digest	83ff658 -> 6b8950b

Source: https://github.com/sourcegraph/sourcegraph/pull/19488

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