Fix character escaping issues during config generation

Many years ago, microsoft#24 attempted to properly escape special characters
in a string by creating its own `Get-EscapedJsonValue` function, but
that only escaped `\`, `\t`, `\r`, `\n`.  That doesn't cover all the
possible characters needing to be encoded though.

At the time, this clearly seemed like a _good_ idea, but looking back
at this code with more experience, it's not clear to me why I didn't
just use `ConvertTo-Json` directly. Doing that now.

One additional update that needed to be done however was to "escape"
in `tag` and `notesForCertification` with '//' with '\\'.  This isn't
_completely_ correct, but not doing so meant that anything after that
would be improperly flagged as a comment by `Remove-Comment` and then
removed.

StoreBroker/Helpers.ps1

@@ -321,57 +321,6 @@ function Get-SHA512Hash
     return [System.BitConverter]::ToString($sha512.ComputeHash($utf8.GetBytes($PlainText))) -replace '-', ''
 }
 
-function Get-EscapedJsonValue
-{
-<#
-    .SYNOPSIS
-        Escapes special characters within a string for use within a JSON value.
-
-    .DESCRIPTION
-        Escapes special characters within a string for use within a JSON value.
-
-        The Git repo for this module can be found here: http://aka.ms/StoreBroker
-
-    .PARAMETER Value
-        The string that needs to be escaped
-
-    .EXAMPLE
-        Get-EscapedJsonValue -Value 'This is my "quote". Look here: c:\windows\'
-
-        Returns back the string 'This is my \"quote\". Look here: c:\\windows\\'
-
-    .OUTPUTS
-        System.String - A string with special characters escaped for use within JSON.
-
-    .NOTES
-        Normalizes newlines and carriage returns to always be \r\n.
-#>
-    [CmdletBinding()]
-    param(
-        [Parameter(
-            Mandatory,
-            ValueFromPipeline)]
-        [AllowNull()]
-        [AllowEmptyString()]
-        [string] $Value
-    )
-
-    # The syntax of -replace is a bit confusing, so it's worth a note here.
-    # The first parameter is a regular expression match pattern.  The second parameter is a replacement string.
-    # So, when we try to do "-replace '\\', '\\", that's matching a single backslash (which has to be
-    # escaped within the match regular expression as a double-backslash), and replacing it with a
-    # string containing literally two backslashes.
-    # (And as a reminder, PowerShell's escape character is actually the backtick (`) and not backslash (\).)
-
-    # \, ", <tab>
-    $escaped = $Value -replace '\\', '\\' -replace '"', '\"' -replace '\t', '\t'
-
-    # Now normalize actual CR's and LF's with their control codes.  We'll ensure all variations are uniformly formatted as \r\n
-    $escaped = $escaped -replace '\r\n', '\r\n' -replace '\r', '\r\n' -replace '\n', '\r\n'
-
-    return $escaped
-}
-
 function ConvertTo-Array
 {
 <#

StoreBroker/PackageTool.ps1

@@ -125,16 +125,16 @@ function Get-StoreBrokerConfigFileContentForIapId
         $updated = $updated -replace '"lifetime": ".*",', "`"lifetime`": `"$($sub.lifetime)`","
         $updated = $updated -replace '"contentType": ".*",', "`"contentType`": `"$($sub.contentType)`","
 
-        $tag = Get-EscapedJsonValue -Value $sub.tag
-        $updated = $updated -replace '"tag": ""', "`"tag`": `"$tag`""
+        $tag = ConvertTo-Json -InputObject ($sub.tag -replace '//', '\\') # Ensure // doesn't get stripped out as a comment later on.
+        $updated = $updated -replace '"tag": ""', "`"tag`": $tag"
 
         $keywords = $sub.keywords | ConvertTo-Json -Depth $script:jsonConversionDepth
         if ($null -eq $keywords) { $keywords = "[ ]" }
         $updated = $updated -replace '(\s+)"keywords": \[.*(\r|\n)+\s*\]', "`$1`"keywords`": $keywords"
 
         # NOTES FOR CERTIFICATION
-        $notesForCertification = Get-EscapedJsonValue -Value $sub.notesForCertification
-        $updated = $updated -replace '"notesForCertification": ""', "`"notesForCertification`": `"$notesForCertification`""
+        $notesForCertification = ConvertTo-Json -InputObject ($sub.notesForCertification -replace '//', '\\') # Ensure // doesn't get stripped out as a comment later on.
+        $updated = $updated -replace '"notesForCertification": ""', "`"notesForCertification`": $notesForCertification"
 
         return $updated
     }
@@ -361,8 +361,8 @@ function Get-StoreBrokerConfigFileContentForAppId
         }
 
         # NOTES FOR CERTIFICATION
-        $notesForCertification = Get-EscapedJsonValue -Value $sub.notesForCertification
-        $updated = $updated -replace '"notesForCertification": ""', "`"notesForCertification`": `"$notesForCertification`""
+        $notesForCertification = ConvertTo-Json -InputObject ($sub.notesForCertification -replace '//', '\\') # Ensure // doesn't get stripped out as a comment later on.
+        $updated = $updated -replace '"notesForCertification": ""', "`"notesForCertification`": $notesForCertification"
 
         return $updated
     }