Bugfix/fix 0 retry times (#981)

## Context
#928 

## Change
Fix endless retry when maxy retry is ste to 0 or negative

## Checklist
Before submitting this PR, please check the following points:
- [x] I have added unit and integration tests for my change
- [x] All unit and integration tests in the module I have added/changed
are green
- [x] All unit and integration tests in the
[core](https://github.com/langchain4j/langchain4j/tree/main/langchain4j-core)
and
[main](https://github.com/langchain4j/langchain4j/tree/main/langchain4j)
modules are green
- [ ] I have added/updated the
[documentation](https://github.com/langchain4j/langchain4j/tree/main/docs/docs)
- [ ] I have added an example in the [examples
repo](https://github.com/langchain4j/langchain4j-examples) (only for
"big" features)
- [ ] I have added my new module in the
[BOM](https://github.com/langchain4j/langchain4j/blob/main/langchain4j-bom/pom.xml)
(only when a new module is added)

langchain4j-core/src/main/java/dev/langchain4j/internal/RetryUtils.java

@@ -191,7 +191,7 @@ public <T> T withRetry(Callable<T> action, int maxAttempts) {
                 try {
                     return action.call();
                 } catch (Exception e) {
-                    if (attempt == maxAttempts) {
+                    if (attempt >= maxAttempts) {
                         throw new RuntimeException(e);
                     }
 

langchain4j-core/src/test/java/dev/langchain4j/internal/RetryUtilsTest.java

@@ -106,4 +106,36 @@ void testMaxAttemptsReached() throws Exception {
         verify(mockAction, times(3)).call();
         verifyNoMoreInteractions(mockAction);
     }
+
+    @Test
+    void testZeroAttemptsReached() throws Exception {
+        @SuppressWarnings("unchecked")
+        Callable<String> mockAction = mock(Callable.class);
+        when(mockAction.call()).thenThrow(new RuntimeException());
+
+        RetryUtils.RetryPolicy policy = RetryUtils.retryPolicyBuilder()
+                .delayMillis(100)
+                .build();
+
+        assertThatThrownBy(() -> policy.withRetry(mockAction, 0))
+                .isInstanceOf(RuntimeException.class);
+        verify(mockAction, times(1)).call();
+        verifyNoMoreInteractions(mockAction);
+    }
+
+    @Test
+    void testIllegalAttemptsReached() throws Exception {
+        @SuppressWarnings("unchecked")
+        Callable<String> mockAction = mock(Callable.class);
+        when(mockAction.call()).thenThrow(new RuntimeException());
+
+        RetryUtils.RetryPolicy policy = RetryUtils.retryPolicyBuilder()
+                .delayMillis(100)
+                .build();
+
+        assertThatThrownBy(() -> policy.withRetry(mockAction, -1))
+                .isInstanceOf(RuntimeException.class);
+        verify(mockAction, times(1)).call();
+        verifyNoMoreInteractions(mockAction);
+    }
 }