Fix various typos in docs (#17114)

### Pull Request Checklist

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(run the
[linters](https://element-hq.github.io/synapse/latest/development/contributing_guide.html#run-the-linters))

1 files changed, 2 insertions, 2 deletions

diff --git a/docs/user_directory.md b/docs/user_directory.md

index 1271cfb862..be8664a016 100644
--- a/docs/user_directory.md
+++ b/docs/user_directory.md
@@ -86,9 +86,9 @@ The search term is then split into words:
 * If unavailable, then runs of ASCII characters, numbers, underscores, and hyphens
   are considered words.
 
-The queries for PostgreSQL and SQLite are detailed below, by their overall goal
+The queries for PostgreSQL and SQLite are detailed below, but their overall goal
 is to find matching users, preferring users who are "real" (e.g. not bots,
-not deactivated). It is assumed that real users will have an display name and
+not deactivated). It is assumed that real users will have a display name and
 avatar set.
 
 ### PostgreSQL