Upgrade JUnit 4.11 (CVE-2020-15250) and consider JUnit 5

[bushidocodes]

pom.xml line 20 pins junit:junit:4.11. This version is affected by CVE-2020-15250: TemporaryFolder creates files with world-readable permissions on Unix, allowing local information disclosure. Bump to 4.13.2 for a one-line fix, or migrate to JUnit Jupiter 5.x. Test scope limits exposure to CI environments but it will surface in any dependency scan.

[bushidocodes]

Closing — pom.xml now uses org.junit.jupiter:junit-jupiter:5.10.1; the old junit:junit:4.11 is gone. Verified against current HEAD.