fix: correct race condition (#1160)

* fix: correct race condition

* fix: make URL parsing test work with Go 1.16

From the release notes in Go 1.17:

The net/url and net/http packages used to accept ";" (semicolon) as a
setting separator in URL queries, in addition to "&" (ampersand). Now,
settings with non-percent-encoded semicolons are rejected and net/http
servers will log a warning to Server.ErrorLog when encountering one in a
request URL.

See "URL query parsing" in https://go.dev/doc/go1.17.

cmd/root_test.go

@@ -149,7 +149,7 @@ func TestNewCommandWithErrors(t *testing.T) {
 		},
 		{
 			desc: "when the query string is bogus",
-			args: []string{"proj:region:inst?ke;y=b;ad"},
+			args: []string{"proj:region:inst?%=foo"},
 		},
 		{
 			desc: "when the address query param is empty",

internal/proxy/proxy.go

@@ -134,10 +134,10 @@ func NewClient(ctx context.Context, d Dialer, cmd *cobra.Command, conf *Config)
 	var mnts []*socketMount
 	pc := newPortConfig(conf.Port)
 	for _, inst := range conf.Instances {
-		go func(i InstanceConnConfig) {
+		go func(name string) {
 			// Initiate refresh operation
-			d.EngineVersion(ctx, inst.Name)
-		}(inst)
+			d.EngineVersion(ctx, name)
+		}(inst.Name)
 	}
 	for _, inst := range conf.Instances {
 		m := &socketMount{inst: inst.Name}