gomod: update zoekt
Created by: keegancsmith
Includes the following commits. In particular we are interested to see if our commit which removes python from the image removes a CVE related to expat.
- https://github.com/sourcegraph/zoekt/commit/9d1b56e change findShard implementation to match on IDs, not names
- https://github.com/sourcegraph/zoekt/commit/f6ba702 ctags: bump version to latest
- https://github.com/sourcegraph/zoekt/commit/840d5e4 docs: document JSON API
- https://github.com/sourcegraph/zoekt/commit/5f70fa0 fix: sourcegraphFake only checks SG_PRIVATE
- https://github.com/sourcegraph/zoekt/commit/abedc19 introduce BLOCK_PROFILE_RATE environment variable to control the sampling rate of Go's block profiler
- https://github.com/sourcegraph/zoekt/commit/acb6f19 use the ctags build script from sourcegraph
- https://github.com/sourcegraph/zoekt/commit/9e4c394 indexserver: track number of repository options we fetch
- https://github.com/sourcegraph/zoekt/commit/6b1df4f build ctags on alpine 3.11
- https://github.com/sourcegraph/zoekt/commit/65df08f specify docker tag versions
- https://github.com/sourcegraph/zoekt/commit/b87be87 debug: add more facilities for debugging
- https://github.com/sourcegraph/zoekt/commit/d19dfcd remove zoekt-merge-small.py
- https://github.com/sourcegraph/zoekt/commit/27e54f1 Add support for JSON responses in the webserver
- https://github.com/sourcegraph/zoekt/commit/574b805 indexserver: return uint from MaybeRemoveMissing
- https://github.com/sourcegraph/zoekt/commit/512672d indexserver: track num of repos we stop tracking
- https://github.com/sourcegraph/zoekt/commit/5bbbd4e merging: run vacuum every 24h instead of every hour
- https://github.com/sourcegraph/zoekt/commit/d11a068 merging: remove obsolete maxSize
- https://github.com/sourcegraph/zoekt/commit/8ec61a4 merging: support unsetting tombstones during cleanup
Test Plan: main dry run for integration tests and to inspect the trivy report to see if expat CVE is gone.