generateInputStream for testing

generateInputStream.kt

    private fun generateInputStream(): InputStream {
        val bytesOutputStream = ByteArrayOutputStream()
        val out = ZipOutputStream(bytesOutputStream, Charset.defaultCharset())
        val writeEntry = ZipEntry("test.csv")
        out.putNextEntry(writeEntry)
        out.write("content".toByteArray())
        out.closeEntry()
        out.close()
        return ByteArrayInputStream(bytesOutputStream.toByteArray())
    }