Auto merge of #24857 - pshaughn:master, r=jdm

add llvm-dev to Debian requirements

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- [ ] `./mach build -d` does not report any errors
- [X] `./mach test-tidy` does not report any errors
- [X] These changes fix #24852 (GitHub issue number if applicable)

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- [ ] There are tests for these changes OR
- [X] These changes do not require tests because it's the build process itself, not servo code

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python/servo/bootstrap.py

@@ -117,7 +117,7 @@ def linux(context, force=False):
                 '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']
+                'ccache', 'clang', 'autoconf2.13', 'libunwind-dev', 'llvm-dev']
     pkgs_dnf = ['libtool', 'gcc-c++', 'libXi-devel', 'freetype-devel', 'libunwind-devel',
                 'mesa-libGL-devel', 'mesa-libEGL-devel', 'glib2-devel', 'libX11-devel',
                 'libXrandr-devel', 'gperf', 'fontconfig-devel', 'cabextract', 'ttmkfdir',