Update get_process_mem to 0.2.3

This squelches a BigDecimal warning in Ruby 2.6:

warning: BigDecimal.new is deprecated; use BigDecimal() method instead.

https://github.com/schneems/get_process_mem/blob/master/CHANGELOG.md

Gemfile.lock

@@ -272,7 +272,7 @@ GEM
       ruby-progressbar (~> 1.4)
     gemojione (3.3.0)
       json
-    get_process_mem (0.2.0)
+    get_process_mem (0.2.3)
     gettext (3.2.9)
       locale (>= 2.0.5)
       text (>= 1.3.0)

changelogs/unreleased/sh-update-process-mem.yml

+---
+title: Update get_process_mem to 0.2.3
+merge_request: 28248
+author:
+type: other