fix whitepsace in DefaultSdkHttpClientBuilder.java

Author: Sean Sullivan

core/sdk-core/src/main/java/software/amazon/awssdk/core/internal/http/loader/DefaultSdkHttpClientBuilder.java

@@ -42,9 +42,9 @@ public SdkHttpClient buildWithDefaults(AttributeMap serviceDefaults) {
                 .map(f -> f.buildWithDefaults(serviceDefaults))
                 .orElseThrow(
                     () -> SdkClientException.builder()
-                                            .message("Unable to load an HTTP implementation from any provider in the" +
-                                                     "chain. You must declare a dependency on an appropriate HTTP" +
-                                                     "implementation or pass in an SdkHttpClient explicitly to the" +
+                                            .message("Unable to load an HTTP implementation from any provider in the " +
+                                                     "chain. You must declare a dependency on an appropriate HTTP " +
+                                                     "implementation or pass in an SdkHttpClient explicitly to the " +
                                                      "client builder.")
                                             .build());
     }