docs: fix link to substitutions

Author: schakko

docs/20-reference/20-backup-definition/10-overview.md

@@ -133,7 +133,7 @@ Variables can be referenced later on in a *file* pattern with help of `${variabl
 
 #### Pattern substitutions
 
-See [Substitutions](substitutions).
+See  [substituions](substitutions).
 
 ### `[$directory].alias`
 If specified, the label `dir` for the epxorted Prometheues metrics will be overwritten with the given alias.
@@ -334,4 +334,4 @@ backmon_backup_file_age_aim_seconds{dir="./backups",disk="_samples/1.postgres-du
 ```mdx-code-block
 </TabItem>
 </Tabs>
-```
+```