Set 600 file permissions to mounted SSH keys

[vinokurig]

What does this PR do?

In order to avoid UNPROTECTED PRIVATE KEY FILE Error while ssh operations, set 600 file permissions level to all mounted SSH keys.

What issues does this PR fix or reference?

#14398

Release Notes

Docs PR

[che-bot]

E2E Happy path tests of Eclipse Che Single User on K8S (minikube v1.1.1) has been successful:

• build details
• logs and configs
• "che-server" docker image: maxura/che-server:14791

[che-bot]

E2E tests of Eclipse Che Multiuser on OCP has failed:

• Build details
• Test report
• docker image: eclipseche/che-server:14791
  https://github.com/orgs/eclipse/teams/eclipse-che-qa please check this report.
  Use command "ci-test" to rerun the test.

[vinokurig]

ci-test

[che-bot]

E2E tests of Eclipse Che Multiuser on OCP has failed:

• Build details
• Test report
• docker image: eclipseche/che-server:14791
  https://github.com/orgs/eclipse/teams/eclipse-che-qa please check this report.
  Use command "ci-test" to rerun the test.

[vinokurig]

ci-test

[che-bot]

E2E tests of Eclipse Che Multiuser on OCP has failed:

• Build details
• Test report
• docker image: eclipseche/che-server:14791
  https://github.com/orgs/eclipse/teams/eclipse-che-qa please check this report.
  Use command "ci-test" to rerun the test.

[vinokurig]

ci-test

[che-bot]

E2E tests of Eclipse Che Multiuser on OCP has failed:

• Build details
• Test report
• docker image: eclipseche/che-server:14791
  https://github.com/orgs/eclipse/teams/eclipse-che-qa please check this report.
  Use command "ci-test" to rerun the test.

[vinokurig]

ci-test

[che-bot]

E2E tests of Eclipse Che Multiuser on OCP has been successful:

• Build details
• Test report
• docker image: eclipseche/che-server:14791