[doc] fix stale measure_G_tau key in svo-csc-plo debugging example

measure_G_tau is not a valid solver key for cthyb (only ctseg/hubbardI);
cthyb always measures G(tau). The obsolete line made the config fail the
unknown-key check in the current input parser.

Author: the-hampel

doc/debugging_examples/svo-csc-plo/dmft_config.toml

@@ -31,7 +31,6 @@ n_warmup_cycles = 10000
 n_cycles_tot = 10e+6
 imag_threshold = 1e-5
 measure_G_l = true
-measure_G_tau = true
 measure_density_matrix = true
 
 [dft]