Clone repository before loading TGM maps.

[benrobson]

Describe the bug
Console spams with a generated exception while booting into TGM if a Maps folder is empty or not present.

Client version
Paper 1.16.5 latest version.

To Reproduce
Steps to reproduce the bug:

1. Remove the /Maps folder.
2. Launch TGM.

Expected behaviour
Thinking the expected behaviour would be if there is no Maps folder or if the folder is empty, clone the repository from the remote.

Screenshots
Plugin TGM v1.0-SNAPSHOT-c4b31bb generated an exception while executing task 538 spams constantly.

[21:54:19 WARN]: [TGM] Plugin TGM v1.0-SNAPSHOT-c4b31bb generated an exception while executing task 538
java.lang.NullPointerException: null
        at network.warzone.tgm.TGM.getModule(TGM.java:192) ~[?:?]
        at network.warzone.tgm.api.ApiManager.lambda$new$0(ApiManager.java:60) ~[?:?]
        at org.bukkit.craftbukkit.v1_16_R3.scheduler.CraftTask.run(CraftTask.java:99) ~[patched_1.16.5.jar:git-Paper-444]
        at org.bukkit.craftbukkit.v1_16_R3.scheduler.CraftAsyncTask.run(CraftAsyncTask.java:54) ~[patched_1.16.5.jar:git-Paper-444]
        at com.destroystokyo.paper.ServerSchedulerReportingWrapper.run(ServerSchedulerReportingWrapper.java:22) ~[patched_1.16.5.jar:git-Paper-444]
        at java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source) [?:1.8.0_281]
        at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source) [?:1.8.0_281]
        at java.lang.Thread.run(Unknown Source) [?:1.8.0_281]
[21:54:20 INFO]: Successfully cloned maps from remote 'official'
[21:54:20 INFO]: Updated sources with remotes. Do /loadmaps to update maps with updated sources

Server Software (Spigot/PaperSpigot):
Whichever Minecraft server software the server is using.