Include all dlerror messages to DllNotFoundException (#70964)

Author: HJLeee

src/coreclr/nativeaot/System.Private.CoreLib/src/System/Runtime/InteropServices/NativeLibrary.NativeAot.Unix.cs

@@ -51,7 +51,14 @@ public void Throw(string libraryName)
 
             public void TrackErrorMessage(string? message)
             {
-                _errorMessage = message;
+                if (_errorMessage == null)
+                {
+                    _errorMessage = Environment.NewLine;
+                }
+                if (!_errorMessage.Contains(message))
+                {
+                    _errorMessage += message + Environment.NewLine;
+                }
             }
         }
     }

src/coreclr/vm/nativelibrary.cpp

@@ -53,6 +53,7 @@ namespace
             LIMITED_METHOD_CONTRACT;
             m_hr = E_FAIL;
             m_priorityOfLastError = 0;
+            m_message = SString(SString::Utf8, "\n");
         }
 
         VOID TrackErrorCode()
@@ -137,7 +138,18 @@ namespace
 
         void SetMessage(LPCSTR message)
         {
+#ifdef TARGET_UNIX
+            //Append dlerror() messages
+            SString new_message = SString(SString::Utf8, message);
+            SString::Iterator i = m_message.Begin();
+            if (!m_message.Find(i, new_message))
+            {
+                m_message += new_message;
+                m_message += SString(SString::Utf8, "\n");
+            }
+#else
             m_message = SString(SString::Utf8, message);
+#endif
         }
 
         HRESULT m_hr;