Update plugin to version 0.4.0 and add release notes (#435)

* Update release notes and plugin description for the marketplace
* Update pluginVersion to 0.4.0

gradle.properties

@@ -4,7 +4,7 @@
 pluginGroup = org.jetbrains.research.testspark
 pluginName = TestSpark
 # SemVer format -> https://semver.org
-pluginVersion = 0.3.1
+pluginVersion = 0.4.0
 
 evosuiteVersion = 1.0.5
 kexVersion = 0.0.8

src/main/resources/META-INF/plugin.xml

@@ -11,20 +11,20 @@
     <p> TestSpark currently supports two test generation strategies:</p>
     <ul>
         <li>LLM-based test generation (using <a href="https://openai.com">OpenAI</a>, HuggingFace, and JetBrains internal AI Assistant platform)</li>
-        <li>Local search-based test generation (using <a href="https://www.evosuite.org">EvoSuite</a>)</li>
+        <li>Local search-based test generation (using <a href="https://www.evosuite.org">EvoSuite</a> and <a href="https://github.com/vorpal-research/kex">Kex</a>)</li>
     </ul>
 
     <h4>LLM-based test generation</h4>
     <p>For this type of test generation, TestSpark sends request to different Large Language Models. Also, it automatically checks if tests are valid before presenting it to users.</p>
-    <p>This feature needs a token from OpenAI, HuggingFace, or the AI Assistant platform.</p>
+    <p>This feature needs a token from OpenAI, HuggingFace, GoogleAI or the AI Assistant platform.</p>
     <ul>
         <li>Supports Java and Kotlin.</li>
         <li>Generates unit tests for capturing failures.</li>
         <li>Generate tests for Java classes, methods, and single lines.</li>
     </ul>
 
     <h4>Local search-based test generation</h4>
-    <p>For this type of test generation, TestSpark uses <a href="https://www.evosuite.org">EvoSuite</a>, which is the  most powerful search-based local test generator. </p>
+    <p>For this type of test generation, TestSpark uses <a href="https://www.evosuite.org">EvoSuite</a>, which is the most powerful search-based local test generator, and <a href="https://github.com/vorpal-research/kex">Kex</a>, which is a symbolic execution engine for Kotlin and Java, developed by Vorpal Research at JetBrains.</p>
     <ul>
         <li>Supports up to Java 11.</li>
         <li>Generates tests for different test criteria: line coverage, branch coverage, I/O diversity, exception coverage, mutation score.</li>
@@ -36,10 +36,17 @@
       ]]></description>
 
     <change-notes><![CDATA[
+        <h4>0.4.0</h4>
+            <ul>
+                <li>Add support for Google AI as an LLM.</li>
+                <li>Add KEX as a new test generation feature.</li>
+                <li>Improve the collection of sample test code candidates.</li>
+                <li>Support IDEA 251.*</li>
+            </ul>
         <h4>0.3.1</h4>
             <ul>
-                <li>Kotlin test generation now works in K2 mode as well./li>
-                <li>Support IDEA 243.*.</li>
+                <li>Kotlin test generation now works in K2 mode as well.</li>
+                <li>Support IDEA 243.*</li>
                 <li>Fixed minor bugs.</li>
             </ul>
         <h4>0.3.0</h4>