Fix py27 job in specs repo

In py27 job index.rst file was checked as any other file if it
contains required headers and sections.
But index.rst file has different format so this file should be
skipped in this test.

After that there was also issue with unexpected "Footnotes"
section in neutron-inter.rst specs so this was also fixed.

Change-Id: If2baf887c49025a5481e97b2fb3500736b8668b6

specs/rocky/neutron-inter.rst

@@ -529,16 +529,10 @@ References
 
 .. _networking-bgpvpn: https://docs.openstack.org/networking-bgpvpn
 .. _networking-l2gw: https://docs.openstack.org/networking-l2gw
-
-Footnotes
-=========
-
 .. [#f1] possible with floating IPs, VPNaaS, but not with the BGP VPN
    interconnections API extension (using a BGPVPN does not require admin
    right, but creating a new BGPVPN does require admin rights)
-
 .. [#f2] possible with VPNaaS, and BGP VPN interconnections, but not with
    floating IPs
-
 .. [#f3] possible with floating IPs and BGP VPN interconnections, but by
    definition not with VPNaaS

tests/test_titles.py

@@ -18,6 +18,7 @@ import testtools
 
 POSTMORTEM = "postmortem"
 STADIUM = "stadium"
+INDEX = "index.rst"
 
 
 class TestTitles(testtools.TestCase):
@@ -116,7 +117,9 @@ class TestTitles(testtools.TestCase):
 
             files = glob.glob("specs/%s/*" % release)
             for filename in files:
-                if POSTMORTEM in filename or STADIUM in filename:
+                if (POSTMORTEM in filename or
+                        STADIUM in filename or
+                        INDEX in filename):
                     continue
                 self.assertTrue(filename.endswith(".rst"),
                                 "spec's file must uses 'rst' extension.")