fix small typo (#33)

Signed-off-by: Akshay Iyyadurai Balasundaram <[email protected]>

README.md

@@ -97,7 +97,7 @@ The tool provides an API endpoint, `/api/v1/metrics`, which returns the usage da
 }
 ```
 
-You can used the following query parameter to filter the list returned:
+You can use the following query parameter to filter the list returned:
 
 * **metric_name**: when used, it will trigger a fuzzy search on the metric_name based on the pattern provided.
 * **used**: when used, will return only the metric used or not (depending on if you set this boolean to true or to false). Leave it empty if you want both.