using GIT_SSH to set credentials jenkins-generated-ssh-key

at org.jenkinsci.plugins.gitclient.CliGitAPIImpl.launchCommandIn(CliGitAPIImpl.java:2318)
at org.jenkinsci.plugins.gitclient.CliGitAPIImpl.launchCommandWithCredentials(CliGitAPIImpl.java:1905)
at org.jenkinsci.plugins.gitclient.CliGitAPIImpl.access$400(CliGitAPIImpl.java:81)
at org.jenkinsci.plugins.gitclient.CliGitAPIImpl$1.execute(CliGitAPIImpl.java:488)
at jenkins.plugins.git.AbstractGitSCMSource.doRetrieve(AbstractGitSCMSource.java:365)
at jenkins.plugins.git.AbstractGitSCMSource.doRetrieve(AbstractGitSCMSource.java:325)
at jenkins.plugins.git.AbstractGitSCMSource.retrieve(AbstractGitSCMSource.java:391)
at jenkins.scm.api.SCMSource.fetch(SCMSource.java:582)
at org.jenkinsci.plugins.workflow.multibranch.SCMBinder.create(SCMBinder.java:98)
at org.jenkinsci.plugins.workflow.job.WorkflowRun.run(WorkflowRun.java:293)
at hudson.model.ResourceController.execute(ResourceController.java:97)
at hudson.model.Executor.run(Executor.java:429)