Check for trailing whitespace

[roll]

Discussed in https://github.com/frictionlessdata/project/discussions/736

^{Originally posted by rgaiacs July 7, 2022} Consider the following CSV file named invalid.csv

id,name,extra
1,english ,
2,english,

Any data visualisation using the above CSV file will have english and english (with trailing whitespace) as categories. Would be great to have a trailing whitespace as part of the baseline check as it will be more clear to learners instead of a constraint error like The cell "english " in row at position "2" and field "name" at position "2" does not conform to a constraint: constraint "pattern" is "^[a-z].*[a-z]$".