getResponseBody() should close Response, so use Response.body().string()

[robinzt]

TeaResponse.getResponseBody() should close okhttp's Response quietly, so use Response.body().string()

Such as alipay-easysdk (java) use TeaResponse.getResponseBody() to get body String, then parsed as json.
But it will be warned by OKHttp: "forget to close a response body"

2021-08-27 11:22:00.686 [OkHttp ConnectionPool] WARN okhttp3.OkHttpClient - 
A connection to https://openapi.alipaydev.com/ was leaked. Did you forget to close a response body? 
To see where this was allocated, set the OkHttpClient logger level to FINE: 
Logger.getLogger(OkHttpClient.class.getName()).setLevel(Level.FINE);

So use Response.body().string() to return body string, and it will be quietly closed Response.
Another benefit: it will handle charset correctly (first from content-type then UTF-8), the original using new String(bytes) but it will use system default charset and maybe not UTF-8.

Related issue:
alipay/alipay-easysdk#269

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[yndu13]

Hi. Thank you for your submission. Have you used this function? As far as I know, this function is not currently in use. We use the getResponse() in most cases.