update sync_externals.csh to pull from coda-oss:main

sync_externals.csh

@@ -1,6 +1,6 @@
-#!/bin/tcsh
+#!/bin/csh -f
 
-git remote add -f coda-oss_remote https://github.com/mdaus/coda-oss.git
+git remote add -f coda-oss_remote git@github.com:mdaus/coda-oss.git
 
 # To set this up the very first time
 # This does a subtree merge and puts it in the externals/coda-oss directory.  --squash avoids copying all the history
@@ -14,9 +14,8 @@ git remote add -f coda-oss_remote https://github.com/mdaus/coda-oss.git
 
 # Now we just want to update
 # Here I'm assuming you're running this on the master branch... otherwise the push command should change
-git subtree pull --prefix externals/coda-oss coda-oss_remote master --squash
+git subtree pull --prefix externals/coda-oss coda-oss_remote main --squash
 
 # If when you do this command you git a merge conflict because a file that has been removed here has been updated in CODA-OSS, you just need to do a 'git rm <pathname>' to resolve the merge conflict.  Then a 'git commit'.
 # TODO: Make this script smart enough to do this.
-
-git push origin master
+# git push origin main