ci/install-{gst, gtk}.sh: reformat to make it more readable

Split commands and strings to multiple lines

Part-of: <https://gitlab.freedesktop.org/gstreamer/gstreamer-rs/-/merge_requests/1176>

ci/install-gst.sh

@@ -5,13 +5,32 @@ pip3 install meson==0.64.1
 # gstreamer-rs already has a 'gstreamer' directory so don't clone there
 pushd .
 cd ..
-git clone --depth 1 https://gitlab.freedesktop.org/gstreamer/gstreamer.git --branch main
+git clone https://gitlab.freedesktop.org/gstreamer/gstreamer.git \
+    --depth 1 \
+    --branch main
+
 cd gstreamer
 
 # plugins required by tests
-PLUGINS="-D gst-plugins-base:ogg=enabled -D gst-plugins-base:vorbis=enabled -D gst-plugins-base:theora=enabled -D gst-plugins-good:matroska=enabled -D gst-plugins-good:vpx=enabled -D gst-plugins-bad:opus=enabled -D gst-plugins-ugly:x264=enabled"
+PLUGINS="-D gst-plugins-base:ogg=enabled \
+         -D gst-plugins-base:vorbis=enabled \
+         -D gst-plugins-base:theora=enabled \
+         -D gst-plugins-good:matroska=enabled \
+         -D gst-plugins-good:vpx=enabled \
+         -D gst-plugins-bad:opus=enabled \
+         -D gst-plugins-ugly:x264=enabled"
 
-meson build -D prefix=/usr/local -D gpl=enabled -D ugly=enabled  -D examples=disabled -D gtk_doc=disabled -D introspection=disabled -D libav=disabled -D python=disabled -D vaapi=disabled $PLUGINS
+meson build \
+    -D prefix=/usr/local \
+    -D gpl=enabled \
+    -D ugly=enabled \
+    -D examples=disabled \
+    -D gtk_doc=disabled \
+    -D introspection=disabled \
+    -D libav=disabled \
+    -D python=disabled \
+    -D vaapi=disabled \
+    $PLUGINS
 ninja -C build
 ninja -C build install
 

ci/install-gtk4.sh

@@ -7,7 +7,10 @@ BRANCH=4.8.2
 git clone https://gitlab.gnome.org/GNOME/gtk.git --branch $BRANCH --depth=1
 cd gtk
 
-meson build -D prefix=/usr/local -Dbuild-tests=false -Dwayland-protocols:tests=false
+meson build \
+    -D prefix=/usr/local \
+    -Dbuild-tests=false  \
+    -Dwayland-protocols:tests=false
 ninja -C build
 ninja -C build install
 cd ..