Sinhala wordlists contain defective test texts

Sinhala [wordlist](https://raw.githubusercontent.com/googlefonts/diffenator2/refs/heads/main/src/diffenator2/data/wordlists/Sinhala.txt) contain 'invalid', defective and wrong test strings that might indicate shaping errors to a non-native reader. (ie; https://github.com/google/fonts/pull/9914)

Few examplaes
`
‍ෙ‍මා්ල් 
 ‍ෝජනා
`