patch 8.2.0641: Vim9:  not expanded in :hardcopy and syn-include

Problem:    Vim9:  not expanded in :hardcopy and "syntax include".
Solution:   Add the EX_EXPAND flag.  Expend "syntax include".
diff --git a/src/vim9execute.c b/src/vim9execute.c
index 7172718..9ea7daf 100644
--- a/src/vim9execute.c
+++ b/src/vim9execute.c
@@ -645,6 +645,7 @@
 	{
 	    // execute Ex command line
 	    case ISN_EXEC:
+		SOURCING_LNUM = iptr->isn_lnum;
 		do_cmdline_cmd(iptr->isn_arg.string);
 		break;
 
@@ -682,6 +683,7 @@
 			}
 		    }
 
+		    SOURCING_LNUM = iptr->isn_lnum;
 		    do_cmdline_cmd(cmd);
 		    vim_free(cmd);
 		}