Spack recipe updates

[AlexanderRichert-NOAA]

g2c could use a round of Spack recipe updates. Recent wgrib2 versions use g2c@2.2, which isn't present the recipe in main Spack (currently it's forced to use g2c@develop), so after the 2.3.0 release would be a good time for some Spack recipe updates (g2c repo+main Spack+JCSDA fork).

[Hang-Lei-NOAA]

Okay, I will make the change after the g2c/2.3.0 and wgrib2/3.8.0 delivered.

[AlysonStahl-NOAA]

I just want to note here that wgrib2 3.8.0 will require g2c 2.3.0. Will g2c need spack updates before wgrib2-v3.8.0 can be released?