Fix typos in VariantShredding

Author: ostronaut

VariantShredding.md

@@ -38,7 +38,7 @@ All field names of a Variant, whether shredded or not, must be present in the me
 
 ## Value Shredding
 
-Variant values that are stored in Parquet fields named `value`.
+Variant values are stored in Parquet fields named `value`.
 Each `value` field may have an associated shredded field named `typed_value` that stores the value when it matches a specific type.
 When `typed_value` is present, readers **must** reconstruct shredded values according to this specification.