Reject trailing characters in DecimalLocaleConverter.parse

[rootvector2]

DecimalLocaleConverter.parse calls DecimalFormat.parse(String), which stops at the first character it cannot read and silently drops the rest, so a locale numeric conversion of 123abc returns 123 and 42 OR 1=1 returns 42. Every numeric locale converter (Byte/Short/Integer/Long/Float/Double/BigDecimal/BigInteger) routes through this one method, while the sibling DateLocaleConverter and the non-locale NumberConverter already reject leftover input with a ParsePosition check. Found by comparing the locale number parsers against DateLocaleConverter; switched to that same check so the whole string must be consumed.

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[garydgregory]

Hello @rootvector2
Please review the failing tests. TY!

[rootvector2]

Those were the existing (B) assertions that pinned DecimalFormat's partial parse of wrong-format input (e.g. 1,234.56 -> 1.234). Now that the whole string has to be consumed, those inputs fall through to the converter default, so I updated the expected values and the now-stale comments across the numeric locale converter tests. mvn test is green.

[garydgregory]

Thank you @rootvector2
Merged 🚀
Would you mind porting this fix to the 1.X branch?

[rootvector2]

Ported to 1.X in #400. Same ParsePosition check, plus the (B) test assertions updated since the wrong-format inputs now fall through to the default.