systems: remove stray break for clang-tidy

clang-tidy warns as follows:

```
/data0/jenkins/workspace/ci-repository/openbmc/bmcweb/redfish-core/lib/systems.hpp:292:13: error: loop will run at most once (loop increment never executed) [clang-diagnostic-unreachable-code-loop-increment,-warnings-as-errors]
            for (const auto& connection : connectionNames)
```

It seems as though the break is stray so remove it.

Signed-off-by: Patrick Williams <patrick@stwcx.xyz>
Change-Id: Iafafb6634819a7f37a1cdd9c4a93e1c426d5dfc5