Cache less in Github Actions workflow

The current cache bundle is greater than MAX_INT32, which apparently works but then fails
to decompress and thus is completely useless.

Instead, just cache the joined/remapped Minecraft jars, remapped libraries, and assets,
which are the slowest/flakiest parts.

Normal libraries such as fastutil, etc. will be redownloaded each time.

Dummy bumps build.gradle to bust the existing cache.

.github/workflows/gradle.yml

@@ -18,8 +18,9 @@ jobs:
       uses: actions/cache@v2
       with:
         path: |
-          ~/.gradle/caches
-          ~/.gradle/wrapper
+          ~/.gradle/caches/VanillaGradle/
+          ~/.gradle/caches/fabric-loom/
+          ~/.gradle/caches/forge_gradle/
           ./.gradle/loom-cache/remapped-mods
         key: ${{ runner.os }}-gradle-${{ hashFiles('**/build.gradle', '**/gradle-wrapper.properties') }}
     - name: Check lang files

build.gradle

@@ -13,7 +13,6 @@ subprojects {
 
     repositories {
         mavenCentral()
-
         maven {
             name = 'Sponge / Mixin'
             url = 'https://repo.spongepowered.org/repository/maven-public/'