Fix capitalization of GitHub in dev module's name

PowerShellGitHubDev.psm1

@@ -1,4 +1,4 @@
-function Start-DevPSGithub
+function Start-DevPSGitHub
 {
     param(
         [switch]$ZapDisable,
@@ -55,4 +55,4 @@ function Start-DevPSGithub
             ri env:COMPLUS_ZapDisable
         }
     }
-}
+}

appveyor.yml

@@ -34,9 +34,9 @@ test_script:
       # For now we don't fail the build if these tests failed
       #
       # FullCLR
-      Import-Module .\PowerShellGithubDev.psm1
+      Import-Module .\PowerShellGitHubDev.psm1
       $testResultsFile = ".\TestsResults.FullCLR.xml"
-      Start-DevPSGithub -binDir $pwd\binFull -NoNewWindow -ArgumentList '-command', "Import-Module .\src\Microsoft.PowerShell.Linux.Host\Modules\Pester; Invoke-Pester test/fullCLR -OutputFormat NUnitXml -OutputFile $testResultsFile"
+      Start-DevPSGitHub -binDir $pwd\binFull -NoNewWindow -ArgumentList '-command', "Import-Module .\src\Microsoft.PowerShell.Linux.Host\Modules\Pester; Invoke-Pester test/fullCLR -OutputFormat NUnitXml -OutputFile $testResultsFile"
       (New-Object 'System.Net.WebClient').UploadFile("https://ci.appveyor.com/api/testresults/nunit/$($env:APPVEYOR_JOB_ID)", (Resolve-Path $testResultsFile))
       # we want to fail the build, if these tests failed
       $x = [xml](cat -raw .\TestsResults.FullCLR.xml)