fix: Flagsmith provider no key exception (#98)

Signed-off-by: Vladimir Petrusevici <[email protected]>
Signed-off-by: vpetrusevici <[email protected]>
Co-authored-by: Vladimir Petrusevici <[email protected]>

Author: vpetrusevici

src/OpenFeature.Contrib.Providers.Flagsmith/FlagsmithProvider.cs

@@ -65,7 +65,12 @@ public FlagsmithProvider(IFlagsmithProviderConfiguration providerOptions, IFlags
 
         private Task<IFlags> GetFlags(EvaluationContext ctx)
         {
-            var key = ctx?.GetValue(Configuration.TargetingKey)?.AsString;
+            string key = null;
+            if (ctx != null && ctx.TryGetValue(Configuration.TargetingKey, out var value))
+            {
+                key = value?.AsString;
+            }
+
             return string.IsNullOrEmpty(key)
                 ? _flagsmithClient.GetEnvironmentFlags()
                 : _flagsmithClient.GetIdentityFlags(key, ctx.AsDictionary().Select(x => new Trait(x.Key, x.Value.AsObject) as ITrait).ToList());