Remove stack traces on EXIT

[iilyak]

Overview

We've noticed that http client in some cases getting a stacktrace. This problem
can be reproduced when shard files are truncated and user try to call /_all_docs.
The depth of the stack trace was not sufficient to uncover that the error is
coming from
couch_mrview:all_docs_fold/4

We've made a hypothesis that we are getting an EXIT whenever we call a
gen_server from the request process.

As a confirmation of this hypothesis there was an error logged from
rexi_server:init_p/3.

[error] 2021-01-28T17:06:16.357719Z [email protected] <0.2558.0> f674d6062d rexi_server:
   from: [email protected](<0.2485.0>)
   mfa: fabric_rpc:all_docs/3
   error:
   {{badmatch,{'EXIT',{{badmatch,eof},[
       {couch_file,read_raw_iolist_int,3,[{file,"src/couch_file.erl"},{line,713}]},

The rexi_server is just one of such places. There might be other places as well.
Even if we would find all such cases in the code base and add special handling to
unwrap the error to remove EXIT. It will not solve the problem because calls
to gen_server can be done in EPI plugin.

Therefore it is better to handle in one place in chttpd:error_info/1.

Co-authored-by: @janosgyerman

Testing recommendations

1. create database
2. add few documents
3. truncate all shards of a database
4. issue /_all_docs request
5. verify that error response doesn't include the stacktrace

Related Issues or Pull Requests

• Remove stack traces from HTTP responses #3363

Checklist

• Code is written and works correctly
• Changes are covered by tests
• Any new configurable parameters are documented in rel/overlay/etc/default.ini
• A PR for documentation changes has been made in https://github.com/apache/couchdb-documentation