Flaky test: test &Oidcc.client_credentials_token/2 works (Oidcc.TokenTest)

### oidcc version

b3bb1a9e31905ca52f372b963c968acd3b12c640

### Erlang version

27.0.1

### Elixir version

1.17.2

### Summary

There is a flaky test.

### Current behavior

occassionally this test fails

```
1) test &Oidcc.client_credentials_token/2 works (Oidcc.TokenTest)
test/oidcc/token_test.exs:211
match (=) failed
code: assert {:ok, %Token{}} =
Oidcc.Token.client_credentials(
client_context,
%{scope: ["openid"]}
)
left: {:ok, %Oidcc.Token{}}
right: {:error, :no_matching_key}
stacktrace:
test/oidcc/token_test.exs:224: (test)
```

### How to reproduce

```
mix test
```

### Expected behavior

all tests should pass