Fixes #315: use ARG and ENV

[rngadam]

Fixes #315

[rngadam]

Before:

 => => naming to docker.io/library/von-network-base    
3 warnings found (use docker --debug to expand):
 - UndefinedVar: Usage of undefined variable '$LOG_LEVEL' (line 3)
 - LegacyKeyValueFormat: "ENV key=value" should be used instead of legacy "ENV key value" format (line 3)
 - LegacyKeyValueFormat: "ENV key=value" should be used instead of legacy "ENV key value" format (line 4)

after:

 => => writing image sha256:f96bfa6d6275dac24adcd45f28cccc4a6959d7b4924e1286a8777eb90b26de9d                                                                                     0.0s
 => => naming to docker.io/library/von-network-base     

still able to override log level by environment variable:

user@9d4a0817476e:~/repos/von-network$ RUST_LOG=warn^[[C LOG_LEVEL=warn ./manage start
[+] Running 5/5
 ✔ Container von-node2-1      Started                                                                                                                                            4.4s 
 ✔ Container von-node3-1      Started                                                                                                                                            4.4s 
 ✔ Container von-node1-1      Started                                                                                                                                            3.7s 
 ✔ Container von-webserver-1  Started                                                                                                                                            3.0s 
 ✔ Container von-node4-1      Started                                                                                                                                            4.2s 
Want to see the scrolling container logs? Run "./manage logs"
user@9d4a0817476e:~/repos/von-network$ ./manage logs
node3-1      | start_indy_node Node3 0.0.0.0 9705 0.0.0.0 9706
node1-1      | start_indy_node Node1 0.0.0.0 9701 0.0.0.0 9702
node1-1      | 2024-08-14 19:21:51,920|WARNING|instance_change_provider.py|InstanceChangeProvider: view_no='lastSentPrePrepare' must be of int type
node2-1      | start_indy_node Node2 0.0.0.0 9703 0.0.0.0 9704
node4-1      | start_indy_node Node4 0.0.0.0 9707 0.0.0.0 9708
node4-1      | 2024-08-14 19:21:52,953|WARNING|instance_change_provider.py|InstanceChangeProvider: view_no='lastSentPrePrepare' must be of int type
node2-1      | 2024-08-14 19:21:53,036|WARNING|instance_change_provider.py|InstanceChangeProvider: view_no='lastSentPrePrepare' must be of int type
node3-1      | 2024-08-14 19:21:53,099|WARNING|instance_change_provider.py|InstanceChangeProvider: view_no='lastSentPrePrepare' must be of int type
webserver-1  | ======== Running on http://0.0.0.0:8000 ========
webserver-1  | (Press CTRL+C to quit)

[WadeBarnes]

@rngadam, Please update your commits to include DCO sign-off. Details here; https://github.com/bcgov/von-network/pull/316/checks?check_run_id=28782287727

[rngadam]

@swcurran done