bugfix? mine grants +1 to laen production.

not certain that this is actually a bug.

res/core/resources/laen.xml

@@ -4,6 +4,7 @@
     <construction skill="mining" minskill="7"/>
   </item>
   <resourcelimit>
+    <modifier building="mine" type="skill" value="1"/>
     <modifier type="require" building="mine"/>
   </resourcelimit>
 </resource>

scripts/tests/e3/production.lua

@@ -38,7 +38,7 @@ function test_laen_needs_mine()
     turn_end()
 end
 
-function bad_test_mine_laen_bonus()
+function test_mine_laen_bonus()
     -- some buildings grant a bonus on the production skill
     -- i.e. a mine adds +1 to mining
     local r = region.create(0, 0, 'mountain')