[Feature]: Drop commons-lang3 dependency and replace its usages with core Java

Feature Description

It would be great if swagger-core would not depend on commons-lang3.

Use Case

Currently swagger-core uses only a few classes from commons-lang3, and it would probably be worth dropping the dependency for the following reasons:

• Better security. commons-* follows "all features in a single jar" pattern, so a CVE in one of the classes would impact swagger-core
• Fewer bytes to ship with binary distribution for the end-users: commons-lang3 is ~690K

I have raised a suggestion to make commons-lang3 modular and extract modules like commons-stringutils, commons-arrayutils, however, Commons team does not seem to like the idea.
Commons PMC members often suggest that users should clone the code or shade commons-lang, see

• https://lists.apache.org/thread/xzdhv57o9rnxtzn5fqbtkzj0hdkbm339
• https://lists.apache.org/thread/9g1opd6l44dmck00b8gwg5qf1srngybl

Suggested Solution (optional)

Use modern Java approaches and remove the use of commons-lang completely.

Alternatives Considered

Ship a micro-module library to replace commons-lang3.

Additional Context

• https://lists.apache.org/thread/xzdhv57o9rnxtzn5fqbtkzj0hdkbm339
• https://lists.apache.org/thread/9g1opd6l44dmck00b8gwg5qf1srngybl
• https://github.com/gradle/gradle/issues/35536
• https://github.com/apache/solr/pull/3823
• https://issues.apache.org/jira/browse/CALCITE-7259

Checklist

• I have searched the existing issues to ensure this is not a duplicate.
• This feature would be useful to more than just my use case.
• I have provided enough detail for the maintainers to understand the scope of the request.

Start by locating the commons-lang3 dependency declaration and every commons-lang3 usage in swagger-core. Read the surrounding code to identify suitable core Java replacements, then run the project's test suite and verify that the dependency is no longer included.