This follows a similar change for local python invocation at https://github.com/serverless/serverless/blob/ad5decb080a7aa92cac1bc0f8632e3e57b99fe46/lib/plugins/aws/invokeLocal/invoke.py#L76-L82

A handler such as the following will now pause at the breakpoint:

```ruby
require 'json'
require 'pry'

def hello(event:, context:)
  binding.pry # breakpoint
  { statusCode: 200, body: JSON.generate('Go Serverless v1.0! Your function executed successfully!') }
end
```

Prior to this, debug output would look something like the following:

```
[1] pry(Kernel)>
f
o
o

=

"
f
o
o
"

=> "foo"

[2] pry(Kernel)>
```

i.e. there's a newline being added after each character is entered, making things somewhat difficult to read.

This reverts commit e30e242.

This breaks a couple of tests which are depending on:

    serverless.cli.consoleLog.lastCall.args[0]

being set.

Also, it introduces an inconsistency c.f. invokeLocalPython et al.

I think here, consistency and passing tests trumps the slight annoyance of each input charact appearing on a new line. At least, for the moment and until a better way is found.