After guest reboot, nfs shared folders are not mounted

### Vagrant version

Vagrant 2.2.9

### Host operating system

Linux/MacOS

### Guest operating system

Linux

### Vagrantfile

```ruby
Vagrant.configure("2") do |config|
config.vm.network :private_network, ip: "172.20.128.2"
config.vm.box = "hashicorp/bionic64"
config.vm.synced_folder "/tests", "/some-tests", type: "nfs"
end
```

### Expected behavior

When system is rebooted, nfs mounts should automatically remount

### Actual behavior

When system is rebooted, nfs mounts do not remount

### Steps to reproduce

```
$ vagrant up
$ vagrant ssh
vagrant@vagrant:$ ls -lah / | grep some-tests
drwxr-xr-x 3 502 dialout 96 Mar 23 17:24 some-tests

vagrant@vagrant:$ ls /some-tests
some-stuff

vagrant@vagrant:$ sudo reboot
$ vagrant ssh
vagrant@vagrant:$ ls -lah / | grep some-tests
drwxr-xr-x 2 root root 4.0K May 21 17:21 some-tests

vagrant@vagrant:$ ls /some-tests
(empty)
```

### References

related to issues
1. https://github.com/hashicorp/vagrant/issues/11368
2. https://github.com/hashicorp/vagrant/issues/11589