Remove numerous extraneous backslash characters

[Adam-S-Daniel]

Replaced 180 instances of "$" with "$", reverting all affected variable mentions to their state from before commit c4201e1

[msftclas]

All CLA requirements met.

[saldana]

⚠️ Validation status: warnings

File	Status	Preview URL	Details
reference/5.1/Microsoft.PowerShell.Core/About/about_Preference_Variables.md	⚠️Warning		Details

reference/5.1/Microsoft.PowerShell.Core/About/about_Preference_Variables.md

• [Warning] Ignore metadata: locale. They are generated by open publish.

For more details, please refer to the build report.

Note: If you changed an existing file name or deleted a file, broken links in other files to the deleted or renamed file are listed only in the full build report.

[sdwheeler]

Those backslash characters are not extraneous. They are required by the tools we use to publish the About topic. Please see Issue #1806 and the updated Style Guide.

[Adam-S-Daniel]

Many of them are visible on the rendered page; they should not be.

[sdwheeler]

Ok. I see some that need to be fixed. The backslash is not needed inside of a code block. I fixed those.

[Adam-S-Daniel]

@sdwheeler - Thank you for pointing out those resources earlier and for addressing this so promptly and thoroughly. When I search the rendered page following your commits ab67cac and b0c3b79, I see that there are now 0 instances of \$ found versus 48 on the previous live version.