fix: revert: use CRC32 to shorten app subdomain

This reverts commit 0e28397c82.

coderd/httpapi/url_test.go

@@ -42,16 +42,6 @@ func TestApplicationURLString(t *testing.T) {
 			},
 			Expected: "8080--agent--workspace--user",
 		},
-		{
-			Name: "LongAppName",
-			URL: httpapi.ApplicationURL{
-				AppSlugOrPort: "0123456789012345678901234567890123456789",
-				AgentName:     "agent",
-				WorkspaceName: "workspace",
-				Username:      "user",
-			},
-			Expected: "app-90667f72",
-		},
 	}
 
 	for _, c := range testCases {