refactor: Break core package into multiple packages under config/endpoint (#759)

* refactor: Partially break core package into dns, result and ssh packages

* refactor: Move core package to config/endpoint

* refactor: Fix warning about overlapping imported package name with endpoint variable

* refactor: Rename EndpointStatus to Status

* refactor: Merge result pkg back into endpoint pkg, because it makes more sense

* refactor: Rename parameter r to result in Condition.evaluate

* refactor: Rename parameter r to result

* refactor: Revert accidental change to endpoint.TypeDNS

* refactor: Rename parameter r to result

* refactor: Merge util package into endpoint package

* refactor: Rename parameter r to result

config/endpoint/ssh/ssh_test.go

@@ -0,0 +1,25 @@
+package ssh
+
+import (
+	"errors"
+	"testing"
+)
+
+func TestSSH_validate(t *testing.T) {
+	cfg := &Config{}
+	if err := cfg.Validate(); err == nil {
+		t.Error("expected an error")
+	} else if !errors.Is(err, ErrEndpointWithoutSSHUsername) {
+		t.Errorf("expected error to be '%v', got '%v'", ErrEndpointWithoutSSHUsername, err)
+	}
+	cfg.Username = "username"
+	if err := cfg.Validate(); err == nil {
+		t.Error("expected an error")
+	} else if !errors.Is(err, ErrEndpointWithoutSSHPassword) {
+		t.Errorf("expected error to be '%v', got '%v'", ErrEndpointWithoutSSHPassword, err)
+	}
+	cfg.Password = "password"
+	if err := cfg.Validate(); err != nil {
+		t.Errorf("expected no error, got '%v'", err)
+	}
+}