dials.refine_bravais_settings: correctly report mI settings

[rjgildea]

Whilst the correct unit cell was being output for I2 settings, the output incorrectly reported this as mC, potentially causing confusion.

Before:

$ dials.refine_bravais_settings indexed.{expt,refl}
...
Chiral space groups corresponding to each Bravais lattice:
aP: P1
mC: C2
+------------+--------------+--------+--------------+----------+-----------+------------------------------------------+----------+---------------+
|   Solution |   Metric fit |   rmsd | min/max cc   |   #spots | lattice   | unit_cell                                |   volume | cb_op         |
|------------+--------------+--------+--------------+----------+-----------+------------------------------------------+----------+---------------|
|   *      2 |       0.0252 |  0.112 | 0.743/0.743  |    18270 | mC        | 44.39  53.14 111.61  90.00  99.76  90.00 |   259466 | a,-b,-a-b-2*c |
|   *      1 |       0      |  0.111 | -/-          |    18292 | aP        | 44.41  53.16  62.42 115.23 101.78  89.99 |   129876 | a,b,c         |
+------------+--------------+--------+--------------+----------+-----------+------------------------------------------+----------+---------------+
* = recommended solution

This PR:

$ dials.refine_bravais_settings indexed.{expt,refl}
...
Chiral space groups corresponding to each Bravais lattice:
aP: P1
mI: I2
+------------+--------------+--------+--------------+----------+-----------+------------------------------------------+----------+---------------+
|   Solution |   Metric fit |   rmsd | min/max cc   |   #spots | lattice   | unit_cell                                |   volume | cb_op         |
|------------+--------------+--------+--------------+----------+-----------+------------------------------------------+----------+---------------|
|   *      2 |       0.0252 |  0.112 | 0.743/0.743  |    18270 | mI        | 44.39  53.14 111.61  90.00  99.76  90.00 |   259466 | a,-b,-a-b-2*c |
|   *      1 |       0      |  0.111 | -/-          |    18292 | aP        | 44.41  53.16  62.42 115.23 101.78  89.99 |   129876 | a,b,c         |
+------------+--------------+--------+--------------+----------+-----------+------------------------------------------+----------+---------------+
* = recommended solution

[dagewa]

Thanks, can confirm this works on the Mpro tutorial

Chiral space groups corresponding to each Bravais lattice:
aP: P1
mI: I2
+------------+--------------+--------+--------------+----------+-----------+------------------------------------------+----------+---------------+
|   Solution |   Metric fit |   rmsd | min/max cc   |   #spots | lattice   | unit_cell                                |   volume | cb_op         |
|------------+--------------+--------+--------------+----------+-----------+------------------------------------------+----------+---------------|
|   *      2 |       0.0252 |  0.112 | 0.743/0.743  |    18270 | mI        | 44.39  53.14 111.61  90.00  99.76  90.00 |   259466 | a,-b,-a-b-2*c |
|   *      1 |       0      |  0.111 | -/-          |    18292 | aP        | 44.41  53.16  62.42 115.23 101.78  89.99 |   129876 | a,b,c         |
+------------+--------------+--------+--------------+----------+-----------+------------------------------------------+----------+---------------+

[dagewa]

I should have noted, this changes the behaviour for the Mpro tutorial a bit, so that text would need updating https://dials.github.io/documentation/tutorials/mpro_x0692.html