add libgtk-3-dev to pre-build step for package workflow

Cargo.toml

@@ -78,25 +78,25 @@ maintenance = { status = "actively-developed" }
 [package.metadata.cross.target.x86_64-unknown-linux-gnu]
 pre-build = [
     "dpkg --add-architecture amd64",
-    "apt update -y && apt install -y libfreetype6-dev:amd64 libexpat1-dev:amd64 libpcap-dev:amd64 libasound2-dev:amd64 libfontconfig1-dev:amd64"
+    "apt update -y && apt install -y libfreetype6-dev:amd64 libexpat1-dev:amd64 libpcap-dev:amd64 libasound2-dev:amd64 libfontconfig1-dev:amd64 libgtk-3-dev:amd64"
 ]
 
 [package.metadata.cross.target.i686-unknown-linux-gnu]
 pre-build = [
     "dpkg --add-architecture i386",
-    "apt update -y && apt install -y libfreetype6-dev:i386 libexpat1-dev:i386 libpcap-dev:i386 libasound2-dev:i386 libfontconfig1-dev:i386"
+    "apt update -y && apt install -y libfreetype6-dev:i386 libexpat1-dev:i386 libpcap-dev:i386 libasound2-dev:i386 libfontconfig1-dev:i386 libgtk-3-dev:i386"
 ]
 
 [package.metadata.cross.target.aarch64-unknown-linux-gnu]
 pre-build = [
     "dpkg --add-architecture arm64",
-    "apt update -y && apt install -y libfreetype6-dev:arm64 libexpat1-dev:arm64 libpcap-dev:arm64 libasound2-dev:arm64 libfontconfig1-dev:arm64"
+    "apt update -y && apt install -y libfreetype6-dev:arm64 libexpat1-dev:arm64 libpcap-dev:arm64 libasound2-dev:arm64 libfontconfig1-dev:arm64 libgtk-3-dev:arm64"
 ]
 
 [package.metadata.cross.target.armv7-unknown-linux-gnueabihf]
 pre-build = [
     "dpkg --add-architecture armhf",
-    "apt update -y && apt install -y libfreetype6-dev:armhf libexpat1-dev:armhf libpcap-dev:armhf libasound2-dev:armhf libfontconfig1-dev:armhf"
+    "apt update -y && apt install -y libfreetype6-dev:armhf libexpat1-dev:armhf libpcap-dev:armhf libasound2-dev:armhf libfontconfig1-dev:armhf libgtk-3-dev:armhf"
 ]
 
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README.md

@@ -233,13 +233,13 @@ Depending on your operating system, you may need to install some dependencies to
   - On [Debian-based](https://en.wikipedia.org/wiki/List_of_Linux_distributions#Debian-based) distributions:
     - `libpcap-dev`
     - `libasound2-dev`
-    - `libgtk-3-dev`
     - `libfontconfig1-dev`
+    - `libgtk-3-dev`
   - On [RPM-based](https://en.wikipedia.org/wiki/List_of_Linux_distributions#RPM-based) distributions:
     - `libpcap-devel`
     - `alsa-lib-devel`
-    - `gtk3-devel`
     - `fontconfig-devel`
+    - `gtk3-devel`
 
 > **Note**
 >