docs: add sha256 checksums for 13.0.6
docs: add sha256 checksums for 13.0.6

Signed-off-by: Emil Velikov <f20878473f414da183da19ee25c8722cc1d711e4@collabora.com>
(cherry picked from commit 879d24c49727cfc6c62cbd5bca58efad4c914e40)

metora/MesaGLSLCompiler,metora/MesaGLSLCompiler,metora/MesaGLSLCompiler