"choco search --allversions" lists very packages and only one version per package

### What is Expected?

When I do `choco search ` and `choco search --allversions` I expect the latter command to output at least the same list of packages as the the former. In addition I expect that the latter lists all versions known for all packages found.

### What You Are Seeing?

`choco search -a` lists _far fewer_ packages than `choco search `.

### How Did You Get This To Happen? (Steps to Reproduce)

Run the following two commands and compare their output:

```
PS C:\WINDOWS\system32> choco search virtualbox
Chocolatey v0.10.15 Professional
virtualbox 6.1.0 [Approved]
VirtualBox.ExtensionPack 5.1.10.20161223 [Approved]
enigmavirtualbox 9.20 [Approved] Downloads cached for licensed users - Possibly broken for FOSS users (due to original download location changes by vendor)
virtualbox-guest-additions-guest.install 6.1.0 [Approved] Downloads cached for licensed users
VBoxHeadlessTray 4.2.0.3
VBoxVmService 6.1 [Approved] Downloads cached for licensed users
multipass 1.0.0 [Approved]
psievm 0.2.7.29815 [Approved]
disk2vhd 2.01.0.20160213 [Approved] Downloads cached for licensed users
packer 1.5.1 [Approved]
vagrant 2.2.6 [Approved] Downloads cached for licensed users
VBoxGuestAdditions.install 99.99.99.99 [Approved]
docker-toolbox 19.03.1 [Approved] Downloads cached for licensed users
13 packages found.
```

vs.

```
PS C:\WINDOWS\system32> choco search virtualbox -a
Chocolatey v0.10.15 Professional
VirtualBox.ExtensionPack 5.1.10.20161223 [Approved]
VBoxGuestAdditions.install 99.99.99.99 [Approved]
2 packages found.
```

It works nicely with other packages (`notepadplusplus` works as expected).

This looks trivial to reproduce, therefore I don't include logs. If you cannot reproduce it with a simple `choco search virtualbox -a`, I'll gladly produce debug logs etc.