build: Bump pipewire dependency

The 0.3.21 release includes busy buffers, which are a requirement
for us to switch to cogl_framebuffer_flush() in the next commit.

Bump pipewire dependency to 0.3.21, and adjust CI to build it from
the corresponding tag.

Part-of: <https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1701>

.gitlab-ci.yml

@@ -12,7 +12,7 @@ stages:
 .mutter.fedora:33@common:
   variables:
     FDO_DISTRIBUTION_VERSION: 33
-    BASE_TAG: '2021-02-04.1'
+    BASE_TAG: '2021-02-04.2'
     FDO_UPSTREAM_REPO: GNOME/mutter
     FDO_DISTRIBUTION_EXEC: |
       dnf install -y 'dnf-command(builddep)' &&
@@ -68,6 +68,20 @@ stages:
           . \
           a9269808f394955f213e34303c2c14fd61c35ab5 &&
 
+      ./.gitlab-ci/install-meson-project.sh \
+          -Dalsa=false \
+          -Dbluez5=false \
+          -Dexamples=false \
+          -Dgstreamer=false \
+          -Djack=false \
+          -Dman=false \
+          -Dpipewire-alsa=false \
+          -Dpipewire-jack=false \
+          -Dsystemd=false \
+          -Dtests=false \
+          https://gitlab.freedesktop.org/pipewire/pipewire.git \
+          0.3.21 . &&
+
       dnf clean all
 
 default:

meson.build

@@ -48,7 +48,7 @@ libinput_req = '>= 1.15.0'
 gbm_req = '>= 17.3'
 
 # screen cast version requirements
-libpipewire_req = '>= 0.3.0'
+libpipewire_req = '>= 0.3.21'
 
 # profiler requirements
 sysprof_req = '>= 3.37.2'