Replaced all instances of HttpStatusCode.TooManyRequests with (HttpStatusCode)429 to ensure compatibility across all target frameworks

Author: msrathore-db

csharp/src/Drivers/Databricks/RetryHttpHandler.cs

@@ -136,7 +136,7 @@ protected override async Task<HttpResponseMessage> SendAsync(
                 request.Content = null;
 
                 // Check if we would exceed the timeout after waiting, based on error type
-                bool isTooManyRequests = response.StatusCode == HttpStatusCode.TooManyRequests;
+                bool isTooManyRequests = response.StatusCode == (HttpStatusCode)429;
                 if (isTooManyRequests)
                 {
                     // Check 429 rate limit timeout
@@ -181,7 +181,7 @@ protected override async Task<HttpResponseMessage> SendAsync(
         private bool IsRetryableStatusCode(HttpStatusCode statusCode)
         {
             // Check too many requests separately
-            if (statusCode == HttpStatusCode.TooManyRequests)         // 429
+            if (statusCode == (HttpStatusCode)429)         // 429 Too Many Requests
                 return _rateLimitRetryEnabled;
 
             // Check other retryable codes

csharp/test/Drivers/Databricks/Unit/RetryHttpHandlerTest.cs

@@ -321,7 +321,7 @@ public async Task RetryHandlerHandlesRateLimitWithSeparateTimeout()
         {
             // Create a mock handler that returns a TooManyRequests (429) response with a Retry-After header
             var mockHandler = new MockHttpMessageHandler(
-                new HttpResponseMessage(HttpStatusCode.TooManyRequests)
+                new HttpResponseMessage((HttpStatusCode)429)
                 {
                     Headers = { { "Retry-After", "1" } },
                     Content = new StringContent("Too Many Requests")
@@ -356,7 +356,7 @@ public async Task RetryHandlerRespectsRateLimitTimeout()
         {
             // Create a mock handler that always returns a TooManyRequests (429) response with a Retry-After header
             var mockHandler = new MockHttpMessageHandler(
-                new HttpResponseMessage(HttpStatusCode.TooManyRequests)
+                new HttpResponseMessage((HttpStatusCode)429)
                 {
                     Headers = { { "Retry-After", "2" } },
                     Content = new StringContent("Too Many Requests")