support old version of core lightnin

[vincenzopalazzo]

Now that the msat are integers from string, we need to support also the old input payload

For instance with v23.02.1 I'm hitting the error

time="2023-05-22T21:52:22Z" level=info msg="Calling update and upload metric"
time="2023-05-22T21:52:22Z" level=debug msg="Calling Update on metrics"
time="2023-05-22T21:52:22Z" level=error msg="invalid character 'd' looking for beginning of value"
time="2023-05-22T21:52:22Z" level=error msg="Error during the listForwards call: decoding JSON fails, this is unexpected invalid character 'd' looking for beginning of value"
time="2023-05-22T21:52:22Z" level=error msg="Error during get the information about the channel: decoding JSON fails, this is unexpected invalid character 'd' looking for beginning of value"
time="2023-05-22T21:52:22Z" level=error msg="Error: decoding JSON fails, this is unexpected invalid character 'd' looking for beginning of value"
time="2023-05-22T21:52:22Z" level=error msg="invalid character '6' looking for beginning of value"
time="2023-05-22T21:52:22Z" level=error msg="Error decoding JSON fails, this is unexpected invalid character '6' looking for beginning of value"
time="2023-05-22T21:52:22Z" level=info msg="Metrics shipped!"
time="2023-05-22T22:22:22Z" level=info msg="Update and Uploading metrics"
time="2023-05-22T22:22:22Z" level=info msg="Calling update and upload metric"
time="2023-05-22T22:22:22Z" level=debug msg="Calling Update on metrics"
time="2023-05-22T22:22:22Z" level=error msg="invalid character '3' looking for beginning of value"
time="2023-05-22T22:22:22Z" level=error msg="Error decoding JSON fails, this is unexpected invalid character '3' looking for beginning of value"
time="2023-05-22T22:22:22Z" level=info msg="Metrics shipped!"
time="2023-05-22T22:52:22Z" level=info msg="Update and Uploading metrics"
time="2023-05-22T22:52:22Z" level=info msg="Calling update and upload metric"
time="2023-05-22T22:52:22Z" level=debug msg="Calling Update on metrics"
time="2023-05-22T22:52:22Z" level=info msg="Call updateMetricOne"
time="2023-05-22T22:52:22Z" level=info msg="Request to URL https://api.lnmetrics.info/query"
time="2023-05-22T22:52:22Z" level=debug msg="Result from server {\"errors\":[{\"message\":\"The server can not verify the payload\",\"path\":[\"updateMetricOne\"]}],\"data\":null}"
time="2023-05-22T22:52:22Z" level=info msg="Request to URL https://api.hedwing.dev/query"
time="2023-05-22T22:52:22Z" level=debug msg="Result from server {\"errors\":[{\"message\":\"The server can not verify the payload\",\"path\":[\"updateMetricOne\"]}],\"data\":null}"
time="2023-05-22T22:52:22Z" level=info msg="Request to URL https://lnmetrics.lndart.dev/query"
time="2023-05-22T22:52:22Z" level=debug msg="Result from server {\"errors\":[{\"message\":\"The server can not verify the payload\",\"path\":[\"updateMetricOne\"]}],\"data\":null}"
time="2023-05-22T22:52:22Z" level=info msg="Metric One Upload at Monday, 22-May-23 22:52:22 UTC"
time="2023-05-22T22:52:22Z" level=info msg="Metrics shipped!"
time="2023-05-22T23:22:22Z" level=info msg="Update and Uploading metrics"
time="2023-05-22T23:22:22Z" level=info msg="Calling update and upload metric"
time="2023-05-22T23:22:22Z" level=debug msg="Calling Update on metrics"
time="2023-05-22T23:22:22Z" level=error msg="expected colon after object key"
time="2023-05-22T23:22:22Z" level=error msg="Error: decoding JSON fails, this is unexpected expected colon after object key"
time="2023-05-22T23:22:22Z" level=error msg="invalid character '3' looking for beginning of value"
time="2023-05-22T23:22:22Z" level=error msg="Error decoding JSON fails, this is unexpected invalid character '3' looking for beginning of value"
time="2023-05-22T23:22:22Z" level=info msg="Metrics shipped!"