[wp] Make sure that wp_plugin/removed uses cache

src/plugins/wp/tests/wp_plugin/oracle_qualif/removed.res.oracle

@@ -15,7 +15,7 @@
 [wp] Loading driver 'share/wp.driver'
 [wp] Warning: Missing RTE guards
 [wp] 1 goal scheduled
-[wp] [Alt-Ergo] Goal typed_main_assert_Eva_signed_overflow : Timeout (unqualified)
+[wp] [Alt-Ergo] Goal typed_main_assert_Eva_signed_overflow : Unsuccess
 [wp] Proved goals:    0 / 1
   Alt-Ergo:        0  (unsuccess: 1)
 [wp] Running WP plugin...

src/plugins/wp/tests/wp_plugin/removed.i

 /* run.config_qualif
-   CMD: @frama-c@ -wp-share ./share -wp-msg-key shell -wp-par 1 -wp-session @PTEST_DIR@/oracle@PTEST_CONFIG@/@PTEST_NAME@.@PTEST_NUMBER@.session -wp-cache replay -wp-cache-dir ./cache
+   CMD: @frama-c@ -wp-share ./share -wp-msg-key shell -wp-par 1 -wp-session @PTEST_DIR@/oracle@PTEST_CONFIG@/@PTEST_NAME@.@PTEST_NUMBER@.session -wp-cache replay -wp-cache-env
    OPT: -eva -eva-msg-key=-summary -then -wp -then -no-eva -warn-unsigned-overflow -wp
  */