Fix key access for collections with spaces in the keys

[Rhohand]

Fixes # .

Changes proposed in this pull request:

• Use double quotes to encase strings for collection access with keys. More details at https://docs.microsoft.com/en-us/previous-versions/windows/it-pro/windows-powershell-1.0/ee692792(v=technet.10)

How to test this code:

• Use a report server with a space in the namespace
• Open a proxy connection
• Invoke New-RsFolder with a new folder
• Expected: Folder is added
• Actual: Line:91 in New-RsFolder will break: $additionalProperties = New-Object System.Collections.Generic.List[$propertyDataType] as there will be a space in the key.

Has been tested on (remove any that don't apply):

• Powershell 5 and above
• Windows 10 and above
• SQL Server 2008 R2 and above

[msftclas]

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[jtarquino]

@Rhohand just waiting for you to sign the license/cla to merge