Algosdk fails parsing JSON from error response when there is no JSON data in the response.

[ashleydavis]

Subject of the issue

Algosdk fails parsing JSON from error response when there is no JSON data in the response.

Steps to reproduce

It's difficult to reproduce but I can show you exactly where the problem is.

Expected behaviour

My sandbox is returning a 504 status code from this route algod/v2/transactions/params.

When calling algoClient.getTransactionParams().do() it should print a reasonable error message.

Actual behaviour

Algosdk attempts to parse JSON data from the error response when there is no JSON data resulting in the following unreasonable error message:

SyntaxError: Unexpected token E in JSON at position 0
    at JSON.parse (<anonymous>)
    at Function.parseJSON (client.ts:125:8)
    at Function.prepareResponse (client.ts:187:12)
    at Function.prepareResponseError (client.ts:209:33)
    at HTTPClient.get (client.js:186:30)
    at processTicksAndRejections (node:internal/process/task_queues:96:5)

The attempt to parse JSON is made here: https://github.com/algorand/js-algorand-sdk/blob/447816198ada99663dbc1c5cfa8df41d9e5124cd/src/client/client.ts#L126

The problem originates from this request here: https://github.com/algorand/js-algorand-sdk/blob/447816198ada99663dbc1c5cfa8df41d9e5124cd/src/client/client.ts#L233

When the sandbox has a problem (for me it is status 504 at the moment) it throws an error with no JSON in the response which is handled here: https://github.com/algorand/js-algorand-sdk/blob/447816198ada99663dbc1c5cfa8df41d9e5124cd/src/client/client.ts#L233

It tries to parse the response from err.response which is not JSON so it throws the aforementioned error.