Update decimal.md (OAI#3208)

Author: ralfhandl

registries/_format/decimal.md

@@ -2,7 +2,7 @@
 owner: baywet
 issue: 889
 description: A fixed point decimal number of unspecified precision and range
-base_type: string|number
+base_type: string number
 layout: default
 remarks: This format is used in a variety of conflicting ways and is not interoperable.
 ---
@@ -25,4 +25,4 @@ The `{{page.slug}}` format represents a fixed point decimal number of unspecifie
 ### Remarks
 
 {{ page.issue }}
-{% endif %}
+{% endif %}