patch 8.2.2823: MS-Windows: launching Vim from installer doesn't open README

Problem:    MS-Windows: launching Vim from installer doesn't open README.
Solution:   Adjust the quotes.
diff --git a/nsis/gvim.nsi b/nsis/gvim.nsi
index 58ed85c..3fe0279 100644
--- a/nsis/gvim.nsi
+++ b/nsis/gvim.nsi
@@ -302,7 +302,7 @@
 
 Function LaunchApplication
    SetOutPath $0
-   ShellExecAsUser::ShellExecAsUser "" "$0\gvim.exe" "-R $"$0\README.txt$""
+   ShellExecAsUser::ShellExecAsUser "" "$0\gvim.exe" '-R "$0\README.txt"'
 FunctionEnd
 
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