Update according to PR suggestions

Author: rickykaare

src/Cabazure.Client.Runtime/Authentication/BearerTokenProvider.cs

@@ -8,7 +8,7 @@ public class BearerTokenProvider : IBearerTokenProvider
     {
         private readonly TokenCredential credential;
         private readonly IDateTimeProvider dateTimeProvider;
-        private readonly ConcurrentDictionary<string[], AccessToken> accessTokenCache = new();
+        private readonly ConcurrentDictionary<string, AccessToken> accessTokenCache = new();
 
         public BearerTokenProvider(
             TokenCredential credential,
@@ -22,9 +22,10 @@ public async Task<AuthenticationHeaderValue> GetTokenAsync(
             string[] scopes,
             CancellationToken cancellationToken)
         {
-            if (!accessTokenCache.TryGetValue(scopes, out var accessToken) || TokenIsExpired(accessToken))
+            var key = string.Join(" ", scopes);
+            if (!accessTokenCache.TryGetValue(key, out var accessToken) || TokenIsExpired(accessToken))
             {
-                accessTokenCache[scopes] = accessToken = await credential.GetTokenAsync(new TokenRequestContext(scopes), cancellationToken);
+                accessTokenCache[key] = accessToken = await credential.GetTokenAsync(new TokenRequestContext(scopes), cancellationToken);
             }
 
             return new AuthenticationHeaderValue(

src/Cabazure.Client.Runtime/HttpRequestMessageExtensions.cs

@@ -2,17 +2,20 @@
 
 public static class HttpRequestMessageExtensions
 {
+    private const string ScopesKey = "scopes";
+
     public static void SetScopes(
         this HttpRequestMessage request,
         params string[] scopes)
-        => request.Properties["scopes"] = scopes;
+        => request.Properties[ScopesKey] = scopes;
 
     public static string[]? GetScopes(this HttpRequestMessage request)
     {
-        if (request.Properties.TryGetValue("scopes", out var value) && value is string[] scopes)
+        if (request.Properties.TryGetValue(ScopesKey, out var value) && value is string[] scopes)
         {
             return scopes;
         }
+
         return null;
     }
 }