Update Sourcegraph Docker images

[renovate]

This PR contains the following updates:

Package	Update	Change
index.docker.io/sourcegraph/cadvisor	digest	8d4cb49 -> 6b7f3d4
index.docker.io/sourcegraph/codeinsights-db	digest	f985af2 -> 75be25e
index.docker.io/sourcegraph/frontend	digest	542e515 -> 423d9d7
index.docker.io/sourcegraph/github-proxy	digest	f47450c -> e8148f3
index.docker.io/sourcegraph/gitserver	digest	172863b -> 320febe
index.docker.io/sourcegraph/indexed-searcher	digest	76d7e8a -> ede7be9
index.docker.io/sourcegraph/jaeger-all-in-one	digest	07c707a -> bbeea94
index.docker.io/sourcegraph/minio	digest	3d7a014 -> 4f39c3f
index.docker.io/sourcegraph/precise-code-intel-worker	digest	4a437a7 -> ca92df3
index.docker.io/sourcegraph/query-runner	digest	caf32e4 -> c3d9a10
index.docker.io/sourcegraph/redis-cache	digest	7820219 -> 35245d8
index.docker.io/sourcegraph/redis-store	digest	e8467a8 -> 5e9fec6
index.docker.io/sourcegraph/repo-updater	digest	6039318 -> fbcdc67
index.docker.io/sourcegraph/search-indexer	digest	89fa7d5 -> 5e9a2f7
index.docker.io/sourcegraph/searcher	digest	33050fe -> 6e00230
index.docker.io/sourcegraph/symbols	digest	8004299 -> 0eac2d3
index.docker.io/sourcegraph/syntax-highlighter	digest	83ff658 -> 8854665
index.docker.io/sourcegraph/worker	digest	c724fc8 -> 293bc78

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