[BUG] Writing Checkpoint with non-zero n_payload_real

[xwgong01]

describe the bug
When the n_payload_real specified by user is not equal to zero, there will be an error writing checkpoint, suggesting that the variable shape is improperly defined.

code version
1.4.0rc

suggested fix

/src/framework/containers/particles_io.cpp
ln. 405-409
io.DefineVariable<real_t>(fmt::format("s%d_pld_r", index()), { adios2::UnknownDim, npld_r() }, { adios2::UnknownDim, 0 }, { adios2::UnknownDim, npld_r() });
should be replaced by the same for pld_i:
io.DefineVariable<npart_t>(fmt::format("s%d_pld_r", index()), { adios2::UnknownDim }, { adios2::UnknownDim }, { adios2::UnknownDim });