Bug 32750: Sign nightly sha256sums files with gpg

tools/ansible/group_vars/boklm-tbb-nightly/tbb-nightly-build.yml

@@ -3,3 +3,4 @@ nightly_build_hostname: f4amtbsowhix7rrf.onion
 nightly_build_url: 'http://{{ nightly_build_hostname }}'
 nightly_build_email_from: "'Tor Browser Nightly Builds (boklm) <boklm-tbb-nightly@riseup.net>',"
 nightly_build_email_to: "[ 'boklm@torproject.org', 'sysrqb@torproject.org', ],"
+nightly_build_sign_build: 1

tools/ansible/roles/tbb-nightly-build/templates/rbm.local.conf

@@ -45,12 +45,14 @@ var:
   local_conf: 1
 
   ### The var/sign_build option defines if you want to sign the
-  ### sha256sums-unsigned-build.txt file with gpg.
-  #sign_build: 1
+  ### sha256sums-unsigned-build.txt and
+  ### sha256sums-unsigned-build.incrementals.txt files with gpg.
+  {% if nightly_build_sign_build is defined %}sign_build: {{ nightly_build_sign_build }}{% endif %}
+
 
   ### The var/sign_build_gpg_opts option can be used to define some gpg
   ### options to select the key to use to sign the sha256sums-unsigned-build.txt
-  ### file.
+  ### and sha256sums-unsigned-build.incrementals.txt files.
   #sign_build_gpg_opts: '--local-user XXXXXXXX'
 
   ### The clean configuration is used by the cleaning script to find the