Intermittent unit test failures in configreload_test

https://github.com/hyperledger/firefly/actions/runs/4567930148/jobs/8062336444?pr=1249

```
--- FAIL: TestConfigDownToNothingOk (0.02s)
manager_test.go:138: PASS: Name()
manager_test.go:138: PASS: InitConfig(string)
manager_test.go:138: PASS: Init(string,string,string,string,string)
manager_test.go:138: PASS: Start()
manager_test.go:140: PASS: Name()
manager_test.go:140: PASS: InitConfig(string)
manager_test.go:140: PASS: Init(string,string)
manager_test.go:140: PASS: SetHandler(string,string)
manager_test.go:140: FAIL: GetNamespace(string,string)
at: [/home/runner/work/firefly/firefly/internal/namespace/configreload_test.go:419 /home/runner/work/firefly/firefly/internal/namespace/configreload_test.go:774]
manager_test.go:140: FAIL: GetNamespace(string,string)
at: [/home/runner/work/firefly/firefly/internal/namespace/configreload_test.go:420 /home/runner/work/firefly/firefly/internal/namespace/configreload_test.go:774]
manager_test.go:140: PASS: GetNamespace(string,string)
manager_test.go:140: FAIL: UpsertNamespace(string,mock.AnythingOfTypeArgument,bool)
at: [/home/runner/work/firefly/firefly/internal/namespace/configreload_test.go:422 /home/runner/work/firefly/firefly/internal/namespace/configreload_test.go:774]
manager_test.go:140: FAIL: 5 out of 8 expectation(s) were met.
The code you are testing needs to make 3 more call(s).
at: [/home/runner/work/firefly/firefly/internal/namespace/manager_test.go:140 /home/runner/work/firefly/firefly/internal/namespace/manager_test.go:281 /home/runner/work/firefly/firefly/internal/namespace/configreload_test.go:804]
manager_test.go:141: PASS: Name()
manager_test.go:141: PASS: InitConfig(string)
manager_test.go:141: PASS: Init(string,string,string)
manager_test.go:141: PASS: Start()
manager_test.go:142: PASS: Name()
manager_test.go:142: PASS: InitConfig(string)
manager_test.go:142: PASS: Init(string,string)
manager_test.go:143: PASS: Name()
manager_test.go:143: PASS: InitConfig(string)
manager_test.go:144: PASS: Name()
manager_test.go:144: PASS: InitConfig(string)
manager_test.go:144: PASS: Init(string,string,string,string)
manager_test.go:144: PASS: Start()
manager_test.go:145: PASS: Name()
manager_test.go:145: PASS: InitConfig(string)
manager_test.go:145: PASS: Init(string,string,string)
manager_test.go:147: PASS: Name()
manager_test.go:147: PASS: InitConfig(string)
manager_test.go:147: PASS: Init(string,string)
manager_test.go:148: PASS: Name()
manager_test.go:148: PASS: InitConfig(string)
manager_test.go:148: PASS: Init(string,string)
manager_test.go:149: PASS: Name()
manager_test.go:149: PASS: InitConfig(string)
manager_test.go:149: PASS: Init(string,string)
manager_test.go:150: FAIL: Init(string,string)
at: [/home/runner/work/firefly/firefly/internal/namespace/configreload_test.go:428 /home/runner/work/firefly/firefly/internal/namespace/configreload_test.go:774]
manager_test.go:150: FAIL: Start()
at: [/home/runner/work/firefly/firefly/internal/namespace/configreload_test.go:439 /home/runner/work/firefly/firefly/internal/namespace/configreload_test.go:774]
manager_test.go:150: PASS: WaitStop()
manager_test.go:150: FAIL: WaitStop()
at: [/home/runner/work/firefly/firefly/internal/namespace/configreload_test.go:788]
manager_test.go:150: FAIL: 1 out of 4 expectation(s) were met.
The code you are testing needs to make 3 more call(s).
at: [/home/runner/work/firefly/firefly/internal/namespace/manager_test.go:150 /home/runner/work/firefly/firefly/internal/namespace/manager_test.go:281 /home/runner/work/firefly/firefly/internal/namespace/configreload_test.go:804]
```