Loopback and WordPress rest api not working due to no connection between the php and the nginx-proxy containers

System Information
- [x] ee cli info
- [x] lsb_release -a
- [x] docker version
- [x] docker-compose version

**### ee cli info:**

OS Linux 5.4.0-77-generic #86-Ubuntu SMP Thu Jun 17 02:35:03 UTC 2021 x86_64
Shell /bin/bash
PHP binary /usr/bin/php7.3
PHP version 7.3.29-1+ubuntu20.04.1+deb.sury.org+1
php.ini used /etc/php/7.3/cli/php.ini
EE root dir phar://ee.phar
EE vendor dir phar://ee.phar/vendor
EE phar path /root
EE packages dir
EE global config /opt/easyengine/config/config.yml
EE project config
EE version 4.3.1

### **lsb_release -a**

No LSB modules are available.
Distributor ID: Ubuntu
Description: Ubuntu 20.04.3 LTS
Release: 20.04
Codename: focal

### **docker version**

Client: Docker Engine - Community
Version: 20.10.8
API version: 1.41
Go version: go1.16.6
Git commit: 3967b7d
Built: Fri Jul 30 19:54:27 2021
OS/Arch: linux/amd64
Context: default
Experimental: true

Server: Docker Engine - Community
Engine:
Version: 20.10.8
API version: 1.41 (minimum version 1.12)
Go version: go1.16.6
Git commit: 75249d8
Built: Fri Jul 30 19:52:33 2021
OS/Arch: linux/amd64
Experimental: false
containerd:
Version: 1.4.9
GitCommit: e25210fe30a0a703442421b0f60afac609f950a3
runc:
Version: 1.0.1
GitCommit: v1.0.1-0-g4144b63
docker-init:
Version: 0.19.0
GitCommit: de40ad0

### **docker-compose version**

ocker-compose version 1.25.0, build unknown
docker-py version: 4.1.0
CPython version: 3.8.10
OpenSSL version: OpenSSL 1.1.1f 31 Mar 2020

Title kinda says it all,
I managed to solve this by either adding one of the above mentioned containers to a bridge network containing the other, or by creating another bridge network just for these two containers. Then adding the ip of the nginx-proxy container to the /etc/hosts of the php container with the domain of the website.

Would love to make a pull request that solves this issue.