Inconsistent error when retrieving a package bound to deleted package

## Environment details:

* local ansible deployment
* version of docker, vagrant, ubuntu, ...
```
→ docker -v
Docker version 18.06.1-ce, build e68fc7a
→ docker-compose -v
docker-compose version 1.15.0, build e12f3b9
→ uname -a
Linux blob 4.10.0-38-generic #42~16.04.1-Ubuntu SMP Tue Oct 10 16:32:20 UTC 2017 x86_64 x86_64 x86_64 GNU/Linux
```
## Steps to reproduce the issue:

1. Create package `p`
```
wsk package create p
```
2. Create package with binding `b` to package `p`
```
wsk package bind p b
```
3. Delete package `p`
```
wsk package delete p
```
4. Get package with binding `b`
```
wsk package get b
```

## Provide the expected results and outputs:

```
$ wsk package get b
error: Unable to get package 'b': Binding references a package that does not exist. (code OTmOOcCT5v8luUz68hlVb8DDPpVHpGya)
```

## Provide the actual results and outputs:

```
$ wsk package get b
error: Unable to get package 'b': The requested resource 'guest/b' does not exist. (code OTmOOcCT5v8luUz68hlVb8DDPpVHpGya)
```

## Additional information you deem important:
* Uncovered by @rabbah in PR #4122