patch 8.2.0267: no check for a following cmd when calling a function fails

Problem:    No check for a following command when calling a function fails.
Solution:   Also check for a following command when inside a try block.
            (closes #5642)
diff --git a/src/userfunc.c b/src/userfunc.c
index 1c25a62..d1d497d 100644
--- a/src/userfunc.c
+++ b/src/userfunc.c
@@ -3554,7 +3554,8 @@
     if (eap->skip)
 	--emsg_skip;
 
-    if (!failed)
+    // When inside :try we need to check for following "| catch".
+    if (!failed || eap->cstack->cs_trylevel > 0)
     {
 	// Check for trailing illegal characters and a following command.
 	if (!ends_excmd(*arg))