docs: add missing word to rectify sentence fragment (#883)

Inserted "that" into "find go functions take" within
`docs/docs/code-search/features.mdx`.

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docs/code-search/features.mdx

@@ -65,7 +65,7 @@ The Sourcegraph search language supports [RE2](https://golang.org/s/re2syntax) s
 - It's well-supported in Go, allowing us to take advantage of a rich ecosystem (notably including [Zoekt](https://github.com/sourcegraph/zoekt))
 - Our API and tooling makes it straightforward to use Sourcegraph with other tools that provide facilities not built in to the search language.
 
-As an example of how you can use Sourcegraph tooling with other tools, we can use `jq` (which supports Perl regexes) along with `src` to post-filter search results. In this case, we want to use backreferences to find go functions take a single pointer argument and return a non-pointer of the same type as the input.
+As an example of how you can use Sourcegraph tooling with other tools, we can use `jq` (which supports Perl regexes) along with `src` to post-filter search results. In this case, we want to use backreferences to find go functions that take a single pointer argument and return a non-pointer of the same type as the input.
 
 ```shell
 re2_regex='func \w+\(\w+ \*\w+\) \w+'