Tutorials: simplify the pull section for the CN5G images

No need to pull every single image independently, we can pull all the images with the corresponding tag that is in the 'docker-compose.yaml' with the 'docker compose pull' command

doc/NR_SA_Tutorial_OAI_CN5G.md

@@ -58,16 +58,8 @@ rm -r ~/openairinterface5g-develop-doc-tutorial_resources-oai-cn5g ~/oai-cn5g.zi
 ## 2.3 Pull OAI CN5G docker images
 
 ```bash
-docker pull mysql:8.0
-docker pull oaisoftwarealliance/oai-amf:develop
-docker pull oaisoftwarealliance/oai-nrf:develop
-docker pull oaisoftwarealliance/oai-smf:develop
-docker pull oaisoftwarealliance/oai-udr:develop
-docker pull oaisoftwarealliance/oai-udm:develop
-docker pull oaisoftwarealliance/oai-ausf:develop
-docker pull oaisoftwarealliance/oai-spgwu-tiny:develop
-docker pull oaisoftwarealliance/trf-gen-cn5g:jammy
-docker pull oaisoftwarealliance/ims:latest
+cd ~/oai-cn5g
+docker compose pull
 ```
 
 # 3. Run OAI CN5G