tests: Fix PKIDIR checks in AT_SKIP.
In Autotest, [xyz] just expands to xyz.  To get [xyz] in output, we
need [[xyz]] in input.
I spotted this based on "expr" reporting an error in testsuite output.
Acked-by: Han Zhou
@@ -548,8 +548,8 @@ AT_SKIP_IF([test "$HAVE_OPENSSL" = no])
# msys on Windows does not convert the path style automatically.
# So, do that forcefully with a 'pwd -W' (called through pwd() function).
PKIDIR="$(cd $abs_top_builddir/tests && pwd)"
-AT_SKIP_IF([expr "$PKIDIR" : ".*[ '\"
-\\]"])
+AT_SKIP_IF([expr "$PKIDIR" : ".*[[ '\"
+\\]]"])
AT_DATA([schema],
[[{"name": "mydb",
"tables": {
