Remove unused options parameter (#6872)

Author: Brian Chen

Firestore/Source/API/FIRDocumentSnapshot.mm

@@ -218,7 +218,7 @@ - (id)convertedValue:(FieldValue)value options:(const FieldValueOptions &)option
     case FieldValue::Type::Double:
       return @(value.double_value());
     case FieldValue::Type::Timestamp:
-      return [self convertedTimestamp:value options:options];
+      return [self convertedTimestamp:value];
     case FieldValue::Type::ServerTimestamp:
       return [self convertedServerTimestamp:value options:options];
     case FieldValue::Type::String:
@@ -238,7 +238,7 @@ - (id)convertedValue:(FieldValue)value options:(const FieldValueOptions &)option
   UNREACHABLE();
 }
 
-- (id)convertedTimestamp:(const FieldValue &)value options:(const FieldValueOptions &)options {
+- (id)convertedTimestamp:(const FieldValue &)value {
   return MakeFIRTimestamp(value.timestamp_value());
 }
 
@@ -250,7 +250,7 @@ - (id)convertedServerTimestamp:(const FieldValue &)value
       return [NSNull null];
     case ServerTimestampBehavior::kEstimate: {
       FieldValue local_write_time = FieldValue::FromTimestamp(sts.local_write_time());
-      return [self convertedTimestamp:local_write_time options:options];
+      return [self convertedTimestamp:local_write_time];
     }
     case ServerTimestampBehavior::kPrevious:
       return sts.previous_value() ? [self convertedValue:*sts.previous_value() options:options]