Remove unmatched '`' from README.rst

This may seem extremely minor, but I'd (jokingly) argue it falls under UX, since I was confused and thought I had dirt on my screen screen due to this lone '`'.
It cost me a whole 5s, then another 5m to write this PR, but if it confuses at least 60 people a day then maybe its worth it?
Anyways, enjoy this extremely minor change that will hopefully eliminate a still really minor annoyance.

Converted from getsops/sops@7f55158

Co-authored-by: Bailey Stevens <me@mtxyz.me>
Signed-off-by: Bailey Stevens <me@mtxyz.me>
Signed-off-by: Felix Fontein <felix@fontein.de>

Author: felixfontein

content/en/docs/_index.md

@@ -1039,7 +1039,7 @@ key service exposed on the unix socket located in `/tmp/sops.sock`, you
 can run:
 
 ``` sh
-$ sops decrypt --keyservice unix:///tmp/sops.sock file.yaml`
+$ sops decrypt --keyservice unix:///tmp/sops.sock file.yaml
 ```
 
 And if you only want to use the key service exposed on the unix socket