Rename and update task file references to 'list-set'

Updated task references in the YAML and Kotlin files to replace 'collections' with 'list-set' for consistency. Removed package generation from template files in DefaultContentProvider and commented out its usage in TaskFileInfo. Renamed the Python template file from 'collections.py' to 'list-set.py'.

Author: Daniil.Karol

ij-plugin/src/main/kotlin/org/jetbrains/research/tasktracker/config/content/task/base/TaskFileInfo.kt

@@ -69,7 +69,7 @@ data class TaskFileInfo(override val filename: String, override val sourceSet: S
             val content = ProgrammingTask::class.java.getResource(fileName)?.readText()
                 ?: error("There are no template file with name '$fileName'")
             val builder = StringBuilder(content)
-            builder.insert(0, DefaultContentProvider.getPackage(extension, path))
+//            builder.insert(0, DefaultContentProvider.getPackage(extension, path))
             return builder.toString()
         }
     }

ij-plugin/src/main/kotlin/org/jetbrains/research/tasktracker/tracking/DefaultContentProvider.kt

@@ -8,7 +8,6 @@ object DefaultContentProvider {
     fun getDefaultContent(extension: Extension?, path: String) = when (extension) {
         Extension.JAVA ->
             """
-                ${getPackage(extension, path)}
                
                 public class Solution {
                 
@@ -23,7 +22,6 @@ object DefaultContentProvider {
 
         Extension.KOTLIN ->
             """
-                ${getPackage(extension, path)}
                 
                 fun main() {
                 

ij-plugin/src/main/resources/org/jetbrains/research/tasktracker/config/content/task/collections.py ij-plugin/src/main/resources/org/jetbrains/research/tasktracker/config/content/task/list-set.py

@@ -32,20 +32,20 @@ tasks:
   - description: "implement function `get_even_numbers_set` that generates and returns a set containing all even numbers between 0 and 100, inclusive."
     id: set
     name: "Even Set"
-    focusFileId: "collections"
+    focusFileId: "list-set"
     files:
-      - filename: collections
+      - filename: list-set
         sourceSet: "SRC"
-        templateFile: "collections"
+        templateFile: "list-set"
         extension: PYTHON
-        id: "collections"
+        id: "list-set"
   - description: "implement function `get_even_numbers_list` that generates and returns a list containing all even numbers between 0 and 100, inclusive."
     id: list
     name: "Even List"
-    focusFileId: "collections"
+    focusFileId: "list-set"
     files:
-      - filename: collections
+      - filename: list-set
         sourceSet: "SRC"
-        templateFile: "collections"
+        templateFile: "list-set"
         extension: PYTHON
-        id: "collections"
+        id: "list-set"