Fix exception handling for parsing errors

[MinnDevelopment]

Pull Request Etiquette

• I have checked the PRs for upcoming features/bug fixes.
• I have read the contributing guidelines.

Changes

• Internal code
• Library interface (affecting end-user code)
• Documentation
• Other: _____

Closes Issue: NaN

Description

This prevents bots from crashing when using complete() if the internal response parsing fails. The Response constructor was trying to re-read the body of the response because we pass in the same (already closed) response when handling exceptions thrown by RestActionImpl#handleResponse.

The stacktrace looks like this:

[15:46:09] [ERROR] Requester: There was an unexpected error while executing a REST request
java.lang.IllegalArgumentException: UNKNOWN_MESSAGE_TYPE
    at net.dv8tion.jda.internal.entities.EntityBuilder.createMessage(EntityBuilder.java:1234)
    at net.dv8tion.jda.api.entities.MessageChannel.lambda$retrieveMessageById$0(MessageChannel.java:896)
    at net.dv8tion.jda.internal.requests.RestActionImpl.handleSuccess(RestActionImpl.java:278)
    at net.dv8tion.jda.internal.requests.RestActionImpl.handleResponse(RestActionImpl.java:268)
    at net.dv8tion.jda.api.requests.Request.handleResponse(Request.java:259)
    at net.dv8tion.jda.internal.requests.Requester.execute(Requester.java:238)
    at net.dv8tion.jda.internal.requests.Requester.execute(Requester.java:142)
    at net.dv8tion.jda.internal.requests.Requester.execute(Requester.java:125)
    at net.dv8tion.jda.internal.requests.ratelimit.BotRateLimiter$Bucket.run(BotRateLimiter.java:478)
    at java.base/java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:515)
    at java.base/java.util.concurrent.FutureTask.run(FutureTask.java:264)
    at java.base/java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.run(ScheduledThreadPoolExecutor.java:304)
    at java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1128)
    at java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:628)
    at java.base/java.lang.Thread.run(Thread.java:834)
[15:46:09] [ERROR] RateLimiter: Encountered exception trying to execute request
java.lang.IllegalStateException: An error occurred while parsing the response for a RestAction
    at net.dv8tion.jda.api.requests.Response.<init>(Response.java:76)
    at net.dv8tion.jda.api.requests.Response.<init>(Response.java:52)
    at net.dv8tion.jda.internal.requests.Requester.execute(Requester.java:261)
    at net.dv8tion.jda.internal.requests.Requester.execute(Requester.java:142)
    at net.dv8tion.jda.internal.requests.Requester.execute(Requester.java:125)
    at net.dv8tion.jda.internal.requests.ratelimit.BotRateLimiter$Bucket.run(BotRateLimiter.java:478)
    at java.base/java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:515)
    at java.base/java.util.concurrent.FutureTask.run(FutureTask.java:264)
    at java.base/java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.run(ScheduledThreadPoolExecutor.java:304)
    at java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1128)
    at java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:628)
    at java.base/java.lang.Thread.run(Thread.java:834)
Caused by: java.io.IOException: closed
    at okio.RealBufferedSource$1.read(RealBufferedSource.java:443)
    at java.base/java.io.BufferedInputStream.fill(BufferedInputStream.java:252)
    at java.base/java.io.BufferedInputStream.read(BufferedInputStream.java:271)
    at java.base/java.util.zip.CheckedInputStream.read(CheckedInputStream.java:60)
    at java.base/java.util.zip.GZIPInputStream.readUByte(GZIPInputStream.java:267)
    at java.base/java.util.zip.GZIPInputStream.readUShort(GZIPInputStream.java:259)
    at java.base/java.util.zip.GZIPInputStream.readHeader(GZIPInputStream.java:165)
    at java.base/java.util.zip.GZIPInputStream.<init>(GZIPInputStream.java:80)
    at java.base/java.util.zip.GZIPInputStream.<init>(GZIPInputStream.java:92)
    at net.dv8tion.jda.internal.utils.IOUtil.getBody(IOUtil.java:243)
    at net.dv8tion.jda.api.requests.Response...