SpringBoot Parsing of image metadata in system tests is broken with newer Paketo builders

Paketo builders made a small change to the format of process info in image metadata, and the Paketo system tests didn't handle the change well.

The old format had an empty array when a process had no args:

"processes": [
    {
        "type": "dist-zip",
        "command": [
            "/workspace/gradle-1745897120691470599-boot/bin/gradle-1745897120691470599"
        ],
        "args": [],
        "direct": false,
        "buildpackID": "paketo-buildpacks/dist-zip"
    },
    {
        "type": "task",
        "command": [
            "/workspace/gradle-1745897120691470599-boot/bin/gradle-1745897120691470599"
        ],
        "args": [],
        "direct": false,
        "buildpackID": "paketo-buildpacks/dist-zip"
    },
    {
        "type": "web",
        "command": [
            "/workspace/gradle-1745897120691470599-boot/bin/gradle-1745897120691470599"
        ],
        "args": [],
        "direct": false,
        "buildpackID": "paketo-buildpacks/dist-zip"
    }
]

The newer format has args: null in these cases.