v2.6.3: Fixes for volcanic emissions

This configuration is for GEOSgcm v12

This release has a bugfix for volcanic emissions. It is non-zero-diff to v2.6.2

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Fixed

• There was a bug where the degassing lat/lon were used to assign emission points for
  explosive volcanic SO2 emissions; this has been corrected.
• There was a bug where the scaling of explosive volcanic SO2 emissions was mistakenely
  being applied to the degassing (effectively further doubling the degassing and not
  correctly scaling the explosive; this has been corrected.

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What's Changed

• Feature/pcolarco/fix volcanic emissions by @pcolarco in #418
• GitFlow: Merge develop into main for v2.6.3 release by @mathomp4 in #426

Full Changelog: v2.6.2...v2.6.3