Ffixing syntax error in installpwsh-amazonlinux.sh (#7905)

* Fix syntax error for issue 7903. Typo come from #6849 

* Add identation after copyright message

tools/installpsh-amazonlinux.sh

@@ -1,4 +1,6 @@
 #!/bin/bash
+# Copyright (c) Microsoft Corporation. All rights reserved.
+# Licensed under the MIT License.
 
 #Companion code for the blog https://cloudywindows.com
 #call this code direction from the web with:
@@ -168,7 +170,7 @@ if [[ "'$*'" =~ preview ]] ; then
 else
     echo "Finding the latest production release"
     release=$(curl https://api.github.com/repos/PowerShell/PowerShell/releases | grep -Po '"tag_name":(\d*?,|.*?[^\\]",)' | grep -Po '\d+.\d+.\d+[\da-z.-]*' | grep -v '[a-z]' | sort | tail -n1)
-if
+fi
 
 #DIRECT DOWNLOAD
 package=powershell-${release}-linux-x64.tar.gz