Make test-strict append to $HGRCPATH, like other tests do since 61fcd9fac434.

tests/test-strict

@@ -1,19 +1,18
 #!/bin/sh
 
 hg init
 
 echo a > a
 hg ci -d '0 0' -Ama
 
 hg an a
 
-HGRCPATH=$HGTMP/.hgrc; export HGRCPATH
-echo "[ui]" >> $HGTMP/.hgrc
-echo "strict=True" >> $HGTMP/.hgrc
+echo "[ui]" >> $HGRCPATH
+echo "strict=True" >> $HGRCPATH
 
 hg an a
 hg annotate a
 
 echo % should succeed - up is an alias, not an abbreviation
 
 hg up