Programmatically create JUnit XML report from "go test" output

Question

I am programmatically calling go test to run tests.

func executeAllTests(c *gin.Context) {
    // Enable verbose
    flag.Set("test.v", "true")
    id := "myUniqueId"

    // Asynchronously run the tests.
    go runTestsAndWriteReport(id)

    // Return
    c.JSON(200, id)
}

func runTestsAndWriteReport(fileName string) {
    testing.Main(
        nil,
        []testing.InternalTest{
            {"TestX", myTestPkg.TestX},
            {"TestY", myTestPkg.TestY}
        },
        nil, nil,
    )

    // TODO: write output as JUnit XML to file "fileName"
}

I would like to write the test output in JUnit XML form to a file. There are frameworks, for example, gotestsum that can do this from the command line, however, I want to do it programmatically as shown above.

Any suggestion on how this can be done?