Fix non-existent DBus1 path in exported CMake target

[remedi]

This commit fixes the issue of SimpleBluez or SimpleDBus failing CMake configuration due to non-existent path in exported target. The issue occurs if DBus1 package files have moved since the installation of these libraries.

SimpleBluez and SimpleDBus should not make assumptions about the location or presence of files provided by DBus1 package. Instead, finding the DBus1 dependency should be done during package configuration by find_dependency() macro.

[CLAassistant]

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