tests: use 'legacy.exchange' option in various bundle1 tests

The new option will stay around. The experimental option was only meant to be
temporary.

tests/test-http-bundle1.t

@@ -4,9 +4,9 b" This test is a duplicate of 'test-http.t"
 parts that are not bundle1/bundle2 specific.
 
   $ cat << EOF >> $HGRCPATH
-  > [experimental]
+  > [devel]
   > # This test is dedicated to interaction through old bundle
-  > bundle2-exp = False
+  > legacy.exchange = bundle1
   > EOF
 
   $ hg init test

tests/test-push-http-bundle1.t

@@ -5,9 +5,9 b' to change with bundle2. Feel free to fac'
 which does not need to exist to keep bundle1 working.
 
   $ cat << EOF >> $HGRCPATH
-  > [experimental]
+  > [devel]
   > # This test is dedicated to interaction through old bundle
-  > bundle2-exp = False
+  > legacy.exchange = bundle1
   > EOF
 
   $ hg init test

tests/test-ssh-bundle1.t

@@ -2,9 +2,9 b" This test is a duplicate of 'test-http.t"
 parts that are not bundle1/bundle2 specific.
 
   $ cat << EOF >> $HGRCPATH
-  > [experimental]
+  > [devel]
   > # This test is dedicated to interaction through old bundle
-  > bundle2-exp = False
+  > legacy.exchange = bundle1
   > [format] # temporary settings
   > usegeneraldelta=yes
   > EOF

tests/test-unbundlehash.t

@@ -3,11 +3,11 b''
 Test wire protocol unbundle with hashed heads (capability: unbundlehash)
 
   $ cat << EOF >> $HGRCPATH
-  > [experimental]
+  > [devel]
   > # This tests is intended for bundle1 only.
   > # bundle2 carries the head information inside the bundle itself and
   > # always uses 'force' as the heads value.
-  > bundle2-exp = False
+  > legacy.exchange = bundle1
   > EOF
 
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