fix: correct OTLP documentation typo (#14602)

Author: josemaia

docs/sources/setup/upgrade/_index.md

@@ -121,7 +121,7 @@ A flagship feature of Loki 3.0 is native support for the Open Telemetry Protocol
 
 Structured Metadata is enabled by default in Loki 3.0, however, it requires your active schema be using both the `tsdb` index type AND the `v13` storage schema.  If you are not using both of these you have two options:
 * Upgrade your index version and schema version before updating to 3.0, see [schema config upgrade](https://grafana.com/docs/loki/<LOKI_VERSION>/operations/storage/schema/).
-* Disable Structured Metadata (and therefor OTLP support) and upgrade to 3.0 and perform the schema migration after. This can be done by setting `allow_structured_metadata: false` in the `limits_config` section or set the command line argument `-validation.allow-structured-metadata=false`.
+* Disable Structured Metadata (and therefore OTLP support) and upgrade to 3.0 and perform the schema migration after. This can be done by setting `allow_structured_metadata: false` in the `limits_config` section or set the command line argument `-validation.allow-structured-metadata=false`.
 
 #### `service_name` label