Adjust tests for changes in Go 1.12.8 / 1.11.13

```
00:38:11 === Failed
00:38:11 === FAIL: opts TestParseDockerDaemonHost (0.00s)
00:38:11     hosts_test.go:87: tcp tcp:a.b.c.d address expected error "Invalid bind address format: tcp:a.b.c.d" return, got "parse tcp://tcp:a.b.c.d: invalid port \":a.b.c.d\" after host" and addr
00:38:11     hosts_test.go:87: tcp tcp:a.b.c.d/path address expected error "Invalid bind address format: tcp:a.b.c.d/path" return, got "parse tcp://tcp:a.b.c.d/path: invalid port \":a.b.c.d\" after host" and addr
00:38:11
00:38:11 === FAIL: opts TestParseTCP (0.00s)
00:38:11     hosts_test.go:129: tcp tcp:a.b.c.d address expected error Invalid bind address format: tcp:a.b.c.d return, got parse tcp://tcp:a.b.c.d: invalid port ":a.b.c.d" after host and addr
00:38:11     hosts_test.go:129: tcp tcp:a.b.c.d/path address expected error Invalid bind address format: tcp:a.b.c.d/path return, got parse tcp://tcp:a.b.c.d/path: invalid port ":a.b.c.d" after host and addr
```

Signed-off-by: Sebastiaan van Stijn <github@gone.nl>
(cherry picked from commit 6837666)
Signed-off-by: Sebastiaan van Stijn <github@gone.nl>

Author: thaJeztah

opts/hosts_test.go

@@ -53,8 +53,8 @@ func TestParseHost(t *testing.T) {
 func TestParseDockerDaemonHost(t *testing.T) {
 	invalids := map[string]string{
 
-		"tcp:a.b.c.d":                   "Invalid bind address format: tcp:a.b.c.d",
-		"tcp:a.b.c.d/path":              "Invalid bind address format: tcp:a.b.c.d/path",
+		"tcp:a.b.c.d":                   "",
+		"tcp:a.b.c.d/path":              "",
 		"udp://127.0.0.1":               "Invalid bind address format: udp://127.0.0.1",
 		"udp://127.0.0.1:2375":          "Invalid bind address format: udp://127.0.0.1:2375",
 		"tcp://unix:///run/docker.sock": "Invalid proto, expected tcp: unix:///run/docker.sock",
@@ -83,7 +83,7 @@ func TestParseDockerDaemonHost(t *testing.T) {
 		"localhost:5555/path":         "tcp://localhost:5555/path",
 	}
 	for invalidAddr, expectedError := range invalids {
-		if addr, err := parseDaemonHost(invalidAddr); err == nil || err.Error() != expectedError {
+		if addr, err := parseDaemonHost(invalidAddr); err == nil || expectedError != "" && err.Error() != expectedError {
 			t.Errorf("tcp %v address expected error %q return, got %q and addr %v", invalidAddr, expectedError, err, addr)
 		}
 	}
@@ -99,8 +99,8 @@ func TestParseTCP(t *testing.T) {
 		defaultHTTPHost = "tcp://127.0.0.1:2376"
 	)
 	invalids := map[string]string{
-		"tcp:a.b.c.d":          "Invalid bind address format: tcp:a.b.c.d",
-		"tcp:a.b.c.d/path":     "Invalid bind address format: tcp:a.b.c.d/path",
+		"tcp:a.b.c.d":          "",
+		"tcp:a.b.c.d/path":     "",
 		"udp://127.0.0.1":      "Invalid proto, expected tcp: udp://127.0.0.1",
 		"udp://127.0.0.1:2375": "Invalid proto, expected tcp: udp://127.0.0.1:2375",
 	}
@@ -125,7 +125,7 @@ func TestParseTCP(t *testing.T) {
 		"localhost:5555/path":         "tcp://localhost:5555/path",
 	}
 	for invalidAddr, expectedError := range invalids {
-		if addr, err := ParseTCPAddr(invalidAddr, defaultHTTPHost); err == nil || err.Error() != expectedError {
+		if addr, err := ParseTCPAddr(invalidAddr, defaultHTTPHost); err == nil || expectedError != "" && err.Error() != expectedError {
 			t.Errorf("tcp %v address expected error %v return, got %s and addr %v", invalidAddr, expectedError, err, addr)
 		}
 	}