mar config show doesn't display TOML sections

Example:

# This is a template for a generic machine configuration with a GNU gcc/gfortran compilers.
# It is always a good starting point for defining a new machine of your own.

# The name is only used for the informative purpose.
machine_id = "any-machine"

# This section defines path to some stored data:
#   - Repository of MAR with source code (validate if a correct branch/commit are used)
#   - Path to a directory with input data required by MAR
#   - Path to a directory with CO2 emission scenarios (RSP/SSP)

input_dir = "~/.mar/input"       # Can be a symbolic link

# Library section tells where are third-party libraries (HDF5, NetCDF-C, NetCDF-Fortran) required by MAR.
# The section defines either, a list of CEA/HPC modules using the `modules` keyword, or
# direct paths to libraries `lib_dir` (*.a, *.so, *.lib, ...) and include files `include_dir` (*.h, *.hpp, *.inc, ...).
# If both methods are used, the `modules` list takes precedence.

lib_dir = "~/.mar/dependencies/lib"         # Can be a symbolic link
include_dir = "~/.mar/dependencies/include" # Can be a symbolic link
#modules = ["module1/v3", "module2/v4"]     # Examples


name = "gnu"
output_preprocessed = false

# Compiler specific compilation flags

nestor = "-static -O3 -w -zero -std=legacy -cpp"
# gfortran 11 doesn't allow for passing INTEGER(8) as REAL(8) arguments (see UNWrite func).
# Unfortunetally, this is done in the current version of MAR source code.
# Hence, we use the `-fallow-argument-mismatch` flag.
mar = "-cpp -g -fallow-argument-mismatch"
radcep = "-fopenmp"


mar = "gomp"
radcep = "gomp"