Scripting: avoid proguarding of slf4j libs in main-kts

slf4j libs are bundled unshadowed to main-kts jar to avoid annoying
slf4j stderr printout (slf4j is used in the maven dependencies resolver)
Exluding it from proguard processing solves problems with using it
directly from scripts.
#KT-60813 fixed
#KT-54819 fixed

libraries/tools/kotlin-main-kts/main-kts.pro

@@ -34,6 +34,9 @@
 -keep class org.apache.maven.wagon.providers.** { *; }
 -keep class org.jetbrains.kotlin.org.apache.maven.wagon.providers.** { *; }
 
+-keep class org.slf4j.** { *; }
+-keep class org.jetbrains.kotlin.org.slf4j.** { *; }
+
 -keepclassmembers class * extends java.lang.Enum {
     <fields>;
     **[] values();