Add Fedora 29 to CI

Modify .gitlab-ci.yml so that every CI pipeline also builds and tests
BIND on Fedora 29.

.gitlab-ci.yml

@@ -64,6 +64,12 @@ stages:
   image: "$CI_REGISTRY_IMAGE:debian-sid-i386"
   <<: *linux_i386
 
+# Fedora
+
+.fedora-29-amd64: &fedora_29_amd64_image
+  image: "$CI_REGISTRY_IMAGE:fedora-29-amd64"
+  <<: *linux_amd64
+
 # Ubuntu
 
 .ubuntu-xenial-amd64: &ubuntu_xenial_amd64_image
@@ -340,6 +346,28 @@ unit:gcc:sid:i386:
   dependencies:
     - gcc:sid:i386
 
+# Jobs for regular GCC builds on Fedora 29 (amd64)
+
+gcc:fedora29:amd64:
+  variables:
+    CC: gcc
+    CFLAGS: "-Wall -Wextra -O2 -g"
+    EXTRA_CONFIGURE: "--with-libidn2"
+  <<: *fedora_29_amd64_image
+  <<: *build_job
+
+system:gcc:fedora29:amd64:
+  <<: *fedora_29_amd64_image
+  <<: *system_test_job
+  dependencies:
+    - gcc:fedora29:amd64
+
+unit:gcc:fedora29:amd64:
+  <<: *fedora_29_amd64_image
+  <<: *unit_test_job
+  dependencies:
+    - gcc:fedora29:amd64
+
 # Jobs for regular GCC builds on Ubuntu 16.04 Xenial Xerus (amd64)
 
 gcc:xenial:amd64: