Fix crashes with CCL, TE tweaks

[jchung01]

Fixed crash in CCL packet fix by removing extra release call. I think in theory having it is necessary, but it deallocates the packet too early if any mod calls any of the sendToXXX methods on the PacketCustom object multiple times. I couldn't really come up with a different way to ensure the packet is released before gc'ed in this particular case (without case-by-case modifications). I tested with -Dio.netty.leakDetection.level=paranoid and didn't seem to find any packet leaks from CCL related networking, so hopefully leaks are still prevented.

Also fixed crash with TE monoculture tweak change - forgot a mod check.

[what-the-diff]

PR Summary

• Enhanced Code Documentations
  Added explanatory comments to the 'UTPacketCustomRetainMixin' class, which specifically focuses on the 'utReleaseOriginal' method. This helps to make the code more readable and easier to understand.

• Updated Import Statements
  Included the necessary import statement for the 'Loader' in the 'UTInsolatorExpansion' class. This is needed to ensure that all required libraries/modules are available for the program to function correctly.

• Updated Method for Better Error Handling
  The 'getFertilizers' method in the 'UTInsolatorExpansion' class is updated to perform additional checks. Before assigning a value to 'fertilizers', it now verifies if the 'additionalFertilizers' list is not null and if the 'crafttweaker' mod is loaded. This addition enhances the robustness of the method by avoiding potential null pointer exceptions or issues related to the non-availability of the 'crafttweaker' mod.