Fix for CVE-2020-2261 in jenkinsci/perfecto-plugin (project jenkinsci__perfecto-plugin_CVE-2020-2261_1.17), commit 52c09ad2e26416211e4009b095c4f16508b27b8a
Fixed file: src/main/java/io/plugins/perfecto/credentials/PerfectoCredentials.java
Fixed class: DescriptorImpl (lines 182-222)
Fixed method: doCheckUserName (lines 222-227)
Method signature: FormValidation doCheckUserName(String)