tests: move chg pager test to test-pager.t

The test is valid for both hg and chg. Since we are adding another chg-related
pager test, let's put them together.

tests/test-chg.t

@@ -15,26 +15,6 b' ill-formed config'
   hg: parse error at * (glob)
   [255]
 
-alias having an environment variable and set to use pager
-
-  $ rm $HGRCPATH
-  $ cat >> $HGRCPATH <<'EOF'
-  > [ui]
-  > formatted = yes
-  > [extensions]
-  > pager =
-  > [pager]
-  > pager = sed -e 's/^/P/'
-  > attend = printa
-  > [alias]
-  > printa = log -T "$A\n" -r 0
-  > EOF
-
-  $ A=1 chg printa
-  P1
-  $ A=2 chg printa
-  P2
-
   $ cp $HGRCPATH.orig $HGRCPATH
   $ cd ..
 

tests/test-pager.t

@@ -189,3 +189,15 b' Pager works with shell aliases.'
   a
   $ hg --config pager.attend-echoa=yes echoa
   paged! 'a\n'
+
+Pager works with hg aliases including environment variables.
+
+  $ cat >> $HGRCPATH <<'EOF'
+  > [alias]
+  > printa = log -T "$A\n" -r 0
+  > EOF
+
+  $ A=1 hg --config pager.attend-printa=yes printa
+  paged! '1\n'
+  $ A=2 hg --config pager.attend-printa=yes printa
+  paged! '2\n'