patch 9.1.1325: tests: not checking error numbers properly

Problem:  tests: not checking error numbers properly.
Solution: Add a trailing comma to avoid matching a different error
          number with the same prefix (zeertzjq)

closes: #17159

Signed-off-by: zeertzjq <zeertzjq@outlook.com>
Signed-off-by: Christian Brabandt <cb@256bit.org>
diff --git a/src/testdir/test_trycatch.vim b/src/testdir/test_trycatch.vim
index 813ad08..31ac6f8 100644
--- a/src/testdir/test_trycatch.vim
+++ b/src/testdir/test_trycatch.vim
@@ -1850,7 +1850,7 @@
       Xpath 'f'
     finally
       Xpath 'g'
-      if caught || $VIMNOERRTHROW && v:errmsg =~ 'E21'
+      if caught || $VIMNOERRTHROW && v:errmsg =~ 'E21:'
         Xpath 'h'
       endif
       break		" discard error for $VIMNOERRTHROW
@@ -1877,7 +1877,7 @@
         Xpath 'k'
       finally
         Xpath 'l'
-        if caught || $VIMNOERRTHROW && v:errmsg =~ 'E21'
+        if caught || $VIMNOERRTHROW && v:errmsg =~ 'E21:'
           Xpath 'm'
         endif
         break		" discard error for $VIMNOERRTHROW
@@ -1896,7 +1896,7 @@
         Xpath 'o'
       finally
         Xpath 'p'
-        if caught || $VIMNOERRTHROW && v:errmsg =~ 'E21'
+        if caught || $VIMNOERRTHROW && v:errmsg =~ 'E21:'
           Xpath 'q'
         endif
         break		" discard error for $VIMNOERRTHROW
@@ -1915,7 +1915,7 @@
         Xpath 's'
       finally
         Xpath 't'
-        if caught || $VIMNOERRTHROW && v:errmsg =~ 'E21'
+        if caught || $VIMNOERRTHROW && v:errmsg =~ 'E21:'
           Xpath 'u'
         endif
         break		" discard error for $VIMNOERRTHROW
@@ -1938,7 +1938,7 @@
         Xpath 'x'
       finally
         Xpath 'y'
-        if caught || $VIMNOERRTHROW && v:errmsg =~ 'E21'
+        if caught || $VIMNOERRTHROW && v:errmsg =~ 'E21:'
           Xpath 'z'
         endif
         break		" discard error for $VIMNOERRTHROW
@@ -1958,7 +1958,7 @@
         Xpath 'B'
       finally
         Xpath 'C'
-        if caught || $VIMNOERRTHROW && v:errmsg =~ 'E21'
+        if caught || $VIMNOERRTHROW && v:errmsg =~ 'E21:'
           Xpath 'D'
         endif
         call assert_equal('a', x)