nxFile - Does not support unsetting suid/sgid/sticky bits via mode parameters

#### Details of the scenario you tried and the problem that is occurring

I used `nxFile` to set a mode of 2740 to set sgid on a directory but I need to remove the sticky bit now.
When I re-run `nxFile` with a mode of 00740 to unset the sticky bits it fails saying 00750 is invalid. But the extra 0 is how chmod is told to clear existing sticky bits.

From the manual page `man chmod` on Ubuntu 22.04:

> For directories chmod preserves set-user-ID and set-group-ID bits unless you explicitly specify otherwise. You can set or clear the bits with symbolic modes like u+s and g-s. To clear these bits for directories with a numeric mode requires an additional leading zero, or leading = like 00755 , or =755

So for directories an extra zero or a leading = are valid specifiers.

#### Verbose logs showing the problem

```shell
root@hostname:/tmp/dsc# pwsh test_dsc.ps1
VERBOSE: Populating RepositorySourceLocation property for module nxtools.
VERBOSE: Loading module from path '/root/.local/share/powershell/Modules/nxtools/1.2.0/nxtools.psm1'.
VERBOSE: The Get-DscResource input 'Name' parameter value is 'nxFile'.
VERBOSE: Skipping resource 'Reason' as it does not match the requested name.
VERBOSE: Creating resource 'nxFile'.
VERBOSE: Skipping resource 'nxGroup' as it does not match the requested name.
VERBOSE: Skipping resource 'nxUser' as it does not match the requested name.
VERBOSE: Skipping resource 'nxPackage' as it does not match the requested name.
VERBOSE: Skipping resource 'nxFileLine' as it does not match the requested name.
VERBOSE: Skipping resource 'nxFileContentReplace' as it does not match the requested name.
VERBOSE: Skipping resource 'nxService' as it does not match the requested name.
VERBOSE: Skipping resource 'nxScript' as it does not match the requested name.
VERBOSE: Skipping resource 'GC_LinuxGroup' as it does not match the requested name.
VERBOSE: Skipping resource 'GC_msid110' as it does not match the requested name.
VERBOSE: Skipping resource 'GC_msid121' as it does not match the requested name.
VERBOSE: Skipping resource 'GC_msid232' as it does not match the requested name.
VERBOSE: Skipping resource 'GC_InstalledApplicationLinux' as it does not match the requested name.
VERBOSE: Skipping resource 'GC_NotInstalledApplicationLinux' as it does not match the requested name.
VERBOSE: Skipping resource 'GC_LinuxLogAnalyticsAgent' as it does not match the requested name.
VERBOSE: output:

VERBOSE: Populating RepositorySourceLocation property for module nxtools.
VERBOSE: Loading module from path '/root/.local/share/powershell/Modules/nxtools/1.2.0/nxtools.psm1'.
VERBOSE: The Get-DscResource input 'Name' parameter value is 'nxFile'.
VERBOSE: Skipping resource 'Reason' as it does not match the requested name.
VERBOSE: Creating resource 'nxFile'.
VERBOSE: Skipping resource 'nxGroup' as it does not match the requested name.
VERBOSE: Skipping resource 'nxUser' as it does not match the requested name.
VERBOSE: Skipping resource 'nxPackage' as it does not match the requested name.
VERBOSE: Skipping resource 'nxFileLine' as it does not match the requested name.
VERBOSE: Skipping resource 'nxFileContentReplace' as it does not match the requested name.
VERBOSE: Skipping resource 'nxService' as it does not match the requested name.
VERBOSE: Skipping resource 'nxScript' as it does not match the requested name.
VERBOSE: Skipping resource 'GC_LinuxGroup' as it does not match the requested name.
VERBOSE: Skipping resource 'GC_msid110' as it does not match the requested name.
VERBOSE: Skipping resource 'GC_msid121' as it does not match the requested name.
VERBOSE: Skipping resource 'GC_msid232' as it does not match the requested name.
VERBOSE: Skipping resource 'GC_InstalledApplicationLinux' as it does not match the requested name.
VERBOSE: Skipping resource 'GC_NotInstalledApplicationLinux' as it does not match the requested name.
VERBOSE: Skipping resource 'GC_LinuxLogAnalyticsAgent' as it does not match the requested name.
RebootRequired
--------------
False
Set-nxMode: Cannot process argument transformation on parameter 'Mode'. Cannot convert value "00740" to type "nxFileSystemMode". Error: "The symbolic string '00740' is invalid."
VERBOSE: output:
False

root@hostname:/tmp/dsc#
```

#### Suggested solution to the issue

Either:
Officially support both #### (4 number) style modes in nxFile so we can set suid/sgid/sticky bits
AND officially support ##### (5 number) style modes so we can unset them
OR
Make it clear that neither 4 or 5 number style modes are supported

#### The DSC configuration that is used to reproduce the issue (as detailed as possible)
```powershell
$commonParamsSetup = @{
Name = 'nxFile'
Property = @{
DestinationPath = '/tmp/testdirectory'
Ensure = 'Present'
Type = 'Directory'
Mode = '7740'
Owner = 'root'
Group = 'root'
Force = $true
}
ModuleName = 'nxTools'
Verbose = $true
}
Invoke-DscResource @commonParamsSetup -Method Set

$commonParamsTest = @{
Name = 'nxFile'
Property = @{
DestinationPath = '/tmp/testdirectory'
Ensure = 'Present'
Type = 'Directory'
Mode = '00740'
Owner = 'root'
Group = 'root'
Force = $true
}
ModuleName = 'nxTools'
Verbose = $true
}
Invoke-DscResource @commonParamsTest -Method Set
```

#### The operating system the target node is running

```shell
/tmp/dsc$ uname -a
Linux hostname 5.19.0-41-generic #42~22.04.1-Ubuntu SMP PREEMPT_DYNAMIC Tue Apr 18 17:40:00 UTC 2 x86_64 x86_64 x86_64 GNU/Linux

/tmp/dsc$ lsb_release -a
No LSB modules are available.
Distributor ID: Ubuntu
Description: Ubuntu 22.04.2 LTS
Release: 22.04
Codename: jammy
```

#### Version and build of PowerShell the target node is running

```
PS /tmp/dsc> $PSVersionTable

Name Value
---- -----
PSVersion 7.3.6
PSEdition Core
GitCommitId 7.3.6
OS Linux 5.19.0-41-generic #42~22.04.1-Ubuntu SMP PREEMPT_DYNAMIC Tue Apr 18 17:40:00 UTC 2
Platform Unix
PSCompatibleVersions {1.0, 2.0, 3.0, 4.0…}
PSRemotingProtocolVersion 2.3
SerializationVersion 1.1.0.1
WSManStackVersion 3.0
```

#### Version of the DSC module that was used

```
PS /tmp/dsc> Get-Module -Name 'nxtools' -ListAvailable | ft Name,Version,Path

Name Version Path
---- ------- ----
nxtools 1.2.0 /root/.local/share/powershell/Modules/nxtools/1.2.0/nxtools.psd1
```