BigInteger parses invalid strings

[fullkomnun]

Describe the bug
When trying to parse invalid strings using BigInteger::parseString it often parses the string successfully
into a numeric value while java's BigInteger throws NumberFormatException

To Reproduce
Steps to reproduce the behavior:
Invoke BigInteger.parseString("a") or BigInteger.parseString("a", 10) both return "10" same as if we invoke BigInteger.parseString("a", 16)

Expected behavior
Java's BigInteger throws NumberFormatException for java.math.BigInteger("a") but parses successfully for java.math.BigInteger("a", 16)

Platform

• JVM

Additional context
Might be relevant for more use-cases of invalid string values.
Might be worth to verify for parsing invalid strings with BigDecimal.