Fix issue when project filenames contains whitespaces

[kwlin]

:sparkles: What kind of change does this PR introduce? (Bug fix, feature, docs update...)

Bug fix

:arrow_heading_down: What is the current behavior?

When the project file name contains whitespaces then NuKeeper fail to restore/remove & add nuget packages.

:new: What is the new behavior (if this is a feature change)?

NuKeeper will execute dotnet restore/remove & add commands with quotations around project file names

:boom: Does this PR introduce a breaking change?

nop

:bug: Recommendations for testing

• Added unittests
• Add a project file name with whitespaces.

:memo: Links to relevant issues/docs

see #1091

:thinking: Checklist before submitting

• [x] All projects build
• [x] Relevant documentation was updated

[kwlin]

@MarcBruins what can I do or help to finish this PR? :)

[stale[bot]]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.

[msallin]

@kwlin can you please rebase the branch on the latest master?