CHS-8047 | Remove calls to deprecated endpoints

Author: kirtigarg2584

src/ContentHubClient.php

@@ -281,7 +281,7 @@ public static function clientNameExists(
     $options['body'] = json_encode(['name' => $name]);
     // Attempt to fetch the client name, if it works.
     try {
-      $client->get("settings/clients/$name");
+      $client->get("settings/client/name/$name");
 
       return TRUE;
     }

test/ContentHubClientTest.php

@@ -523,7 +523,7 @@ public function testClientNameExistsReturnsTrueIfSuccessful(): void {
     $this->guzzle_client
       ->shouldReceive('get')
       ->once()
-      ->with('settings/clients/' . $this->test_data['name']);
+      ->with('settings/client/name/' . $this->test_data['name']);
 
     $exists = $this->ch_client::clientNameExists(
       $this->test_data['name'],
@@ -549,7 +549,7 @@ public function testClientNameExistsReturnsFalseIfCallToPlexusFails(): void {
     $this->guzzle_client
       ->shouldReceive('get')
       ->once()
-      ->with('settings/clients/' . $this->test_data['name'])
+      ->with('settings/client/name/' . $this->test_data['name'])
       ->andThrows(new ClientException('some-message', $request, $response));
 
     $exists = $this->ch_client::clientNameExists(