Run SSH e2e test only if SSH keys are present

Not all CI systems support ssh keys to be present on the node. This
supports the case where "local" provider is being used when running
e2e test, but the environment does not have a SSH key.

test/e2e/framework/util.go

@@ -315,6 +315,12 @@ func SkipIfProviderIs(unsupportedProviders ...string) {
 	}
 }
 
+func SkipUnlessSSHKeyPresent() {
+	if _, err := GetSigner(TestContext.Provider); err != nil {
+		Skipf("No SSH Key for provider %s: '%v'", TestContext.Provider, err)
+	}
+}
+
 func SkipUnlessProviderIs(supportedProviders ...string) {
 	if !ProviderIs(supportedProviders...) {
 		Skipf("Only supported for providers %v (not %s)", supportedProviders, TestContext.Provider)