fix: replace ComboBox's preferredSize with a size of zeroed width…

… and height

It fixes an issue with an input field overflow.

See: https://github.com/JetBrains-Research/TestSpark/pull/343/files#r1781430743

src/main/kotlin/org/jetbrains/research/testspark/display/generatedTests/TestCasePanelBuilder.kt

@@ -306,13 +306,11 @@ class TestCasePanelBuilder(
 
         sendButton.addActionListener { sendRequest() }
 
-        // Set the preferred size of the requestComboBox.
-        // The width is calculated by subtracting the combined heights of languageTextField, requestJLabel,
-        //     sendButton, and a padding of 20 from languageTextField's preferred height.
-        requestComboBox.preferredSize = Dimension(
-            languageTextField.preferredSize.height - requestJLabel.preferredSize.height - sendButton.preferredSize.height - 20,
-            requestComboBox.preferredSize.height
-        )
+        /**
+         * The following code is a workaround for the issue with the ComboBox preferred size.
+         * See: https://github.com/JetBrains-Research/TestSpark/pull/343/files#r1781430743
+         */
+        requestComboBox.preferredSize = Dimension(0, 0)
         requestComboBox.isEditable = true
 
         return panel