Auto merge of #23248 - asajeffrey:liblzma-dev-dependency, r=jdm

Added liblzma-dev dependency on Debian

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This fixes a link error on Debian Linux
```
  = note: /usr/bin/ld.gold: error: cannot find -llzma
          collect2: error: ld returned 1 exit status
```

---
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- [X] `./mach build -d` does not report any errors
- [X] `./mach test-tidy` does not report any errors
- [X] These changes do not require tests because it's a README

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README.md

@@ -90,7 +90,7 @@ If this doesn't work, file a bug, and, run the commands below:
 sudo apt install git curl autoconf libx11-dev \
     libfreetype6-dev libgl1-mesa-dri libglib2.0-dev xorg-dev \
     gperf g++ build-essential cmake virtualenv python-pip \
-    libssl1.0-dev libbz2-dev libosmesa6-dev libxmu6 libxmu-dev \
+    libssl1.0-dev libbz2-dev liblzma-dev libosmesa6-dev libxmu6 libxmu-dev \
     libglu1-mesa-dev libgles2-mesa-dev libegl1-mesa-dev libdbus-1-dev \
     libharfbuzz-dev ccache clang libunwind-dev \
     libgstreamer1.0-dev libgstreamer-plugins-base1.0-dev libgstreamer-plugins-bad1.0-dev autoconf2.13

python/servo/bootstrap.py

@@ -111,7 +111,8 @@ def linux(context, force=False):
     pkgs_apt = ['git', 'curl', 'autoconf', 'libx11-dev', 'libfreetype6-dev',
                 'libgl1-mesa-dri', 'libglib2.0-dev', 'xorg-dev', 'gperf', 'g++',
                 'build-essential', 'cmake', 'python-pip',
-                'libbz2-dev', 'libosmesa6-dev', 'libxmu6', 'libxmu-dev', 'libglu1-mesa-dev',
+                'libbz2-dev', 'liblzma-dev',
+                'libosmesa6-dev', 'libxmu6', 'libxmu-dev', 'libglu1-mesa-dev',
                 'libgles2-mesa-dev', 'libegl1-mesa-dev', 'libdbus-1-dev', 'libharfbuzz-dev',
                 'ccache', 'clang', 'autoconf2.13', "libunwind-dev"]
     pkgs_dnf = ['libtool', 'gcc-c++', 'libXi-devel', 'freetype-devel',