Bump version to 5.6.1

Signed-off-by: shedaniel <daniel@shedaniel.me>

gradle.properties

@@ -1,5 +1,5 @@
 org.gradle.jvmargs=-Xmx3G
-mod_version=5.6.0
+mod_version=5.6.1
 supported_version=1.16.2/3
 minecraft_version=1.16.3
 fabricloader_version=0.9.1+build.205