update script comments

scripts/cask-update.ps1

@@ -12,6 +12,6 @@
 # 4. Environment variables for GITHUB_USER and GITHUB_TOKEN set.
 #
 # To run:
-# ./cask-update.ps1 -version 1.3.0
+# pwsh ./cask-update.ps1 -version 1.3.0
 
 cask-repair --cask-version $version --blind-submit --fail-on-error bitwarden

scripts/snap-update.ps1

@@ -1,5 +1,8 @@
-# To run:
-# ./snap-update.ps1
+# Dependencies:
+# 1. Install powershell, ex `sudo apt-get install -y powershell`
+#
+# To run:
+# pwsh ./snap-update.ps1
 
 $dir = Split-Path -Parent $MyInvocation.MyCommand.Path;
 $rootDir = $dir + "/..";