add missing libdb-dev to debian/tests/control

debian/tests/control

@@ -1,3 +1,3 @@
 Tests: run-tests
 Restrictions: allow-stderr 
-Depends: @, apt, dpkg-dev, debhelper, libdb-dev, gettext, libcurl4-gnutls-dev, zlib1g-dev, libbz2-dev, xsltproc, docbook-xsl, docbook-xml, po4a, autotools-dev, autoconf, automake, doxygen, debiandoc-sgml, stunnel4
+Depends: @, dpkg-dev, debhelper, libdb-dev, gettext, libcurl4-gnutls-dev, zlib1g-dev, libbz2-dev, xsltproc, docbook-xsl, docbook-xml, po4a, autotools-dev, autoconf, automake, doxygen, debiandoc-sgml, stunnel4, libdb-dev