CI workflow for style check

[dreamer2368]

• scripts/stylize.sh now by default checks if stylization is required. If so, it returns error with the list of files that need stylization, without any actual change. For example,

  test@cacca454cccc:~/libROM/scripts$ ./stylize.sh astyle
  Formatted  algo/DMD.cpp
  Formatted  basisComparator.cpp
  Formatted  fileComparator.cpp
  Formatted  solutionComparator.cpp
  Formatted  test_DEIM.cpp
  Formatted  test_GNAT.cpp
  Formatted  test_QDEIM.cpp
  Formatted  test_RandomizedSVD.cpp
  Formatted  test_S_OPT.cpp
  Formatted  dmd/heat_conduction_dmdc.cpp
  Files need stylization!
  Please run stylization before merging the pull-request.
  1. Install Artistic Style Version 3.1
  2. cd scripts && ./stylize.sh -f /path/to/astyle

• For actual enforcement of the stylization, use the flag -f, i.e. ./stylize.sh -f /path/to/astyle.
• Previously stylize.sh checks the out-dated directory tests. Now it checks both unit_tests and regression_tests, which have not been checked so far.

NOTE astyle does not stylize everything for us as intended, and developers should keep the code nice and clean by themselves to some extent. For example, Previously the line 551 of lib/algo/DMD.cpp looks strange due to its peculiarly long line:

    double* inverse_input = new double[d_phi_real_squared->numRows() *
                                                                     d_phi_real_squared->numColumns() * 2];

This is currently edited this way:

    const int dprs_row = d_phi_real_squared->numRows();
    const int dprs_col = d_phi_real_squared->numColumns();
    double* inverse_input = new double[dprs_row * dprs_col * 2];

Potentially there can be more lines that were somewhat carelessly written and might needs some manual edits. This PR does not intend to make all the fixes for this.