Fix build error

Author: kazuki43zoo

src/test/java/org/apache/ibatis/submitted/sqlprovider/ProviderMethodResolutionTest.java

@@ -71,7 +71,7 @@ void shouldErrorWhenDefaultResolverMethodNameMatchedMethodIsNone() {
         () -> sqlSessionFactory.getConfiguration().addMapper(DefaultProvideMethodResolverMethodNameMatchedMethodIsNoneMapper.class));
     assertEquals(
         "Cannot resolve the provider method because 'insert' not found in SqlProvider 'org.apache.ibatis.submitted.sqlprovider.ProviderMethodResolutionTest$DefaultProvideMethodResolverMethodNameMatchedMethodIsNoneMapper$MethodResolverBasedSqlProvider'.",
-        e.getCause().getMessage());
+        e.getMessage());
   }
 
   @Test
@@ -80,7 +80,7 @@ void shouldErrorWhenDefaultResolverReturnTypeMatchedMethodIsNone() {
         () -> sqlSessionFactory.getConfiguration().addMapper(DefaultProvideMethodResolverReturnTypeMatchedMethodIsNoneMapper.class));
     assertEquals(
         "Cannot resolve the provider method because 'insert' does not return the CharSequence or its subclass in SqlProvider 'org.apache.ibatis.submitted.sqlprovider.ProviderMethodResolutionTest$DefaultProvideMethodResolverReturnTypeMatchedMethodIsNoneMapper$MethodResolverBasedSqlProvider'.",
-        e.getCause().getMessage());
+        e.getMessage());
   }
 
   @Test
@@ -89,7 +89,7 @@ void shouldErrorWhenDefaultResolverMatchedMethodIsMultiple() {
         () -> sqlSessionFactory.getConfiguration().addMapper(DefaultProvideMethodResolverMatchedMethodIsMultipleMapper.class));
     assertEquals(
         "Cannot resolve the provider method because 'update' is found multiple in SqlProvider 'org.apache.ibatis.submitted.sqlprovider.ProviderMethodResolutionTest$DefaultProvideMethodResolverMatchedMethodIsMultipleMapper$MethodResolverBasedSqlProvider'.",
-        e.getCause().getMessage());
+        e.getMessage());
   }
 
   @Test
@@ -130,7 +130,7 @@ void shouldErrorWhenCannotDetectsReservedNameMethod() {
         () -> sqlSessionFactory.getConfiguration().addMapper(ReservedNameMethodIsNoneMapper.class));
     assertEquals(
         "Error creating SqlSource for SqlProvider. Method 'provideSql' not found in SqlProvider 'org.apache.ibatis.submitted.sqlprovider.ProviderMethodResolutionTest$ReservedNameMethodIsNoneMapper$SqlProvider'.",
-        e.getCause().getMessage());
+        e.getMessage());
   }
 
   interface ProvideMethodResolverMapper {