Bump appsignal from 4.7.2 to 4.7.3 (#739)

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Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

Author: dependabot[bot]

Gemfile.lock

@@ -111,7 +111,7 @@ GEM
       marcel (>= 1.0.3)
     addressable (2.8.7)
       public_suffix (>= 2.0.2, < 7.0)
-    appsignal (4.7.2)
+    appsignal (4.7.3)
       logger
       rack (>= 2.0.0)
     ast (2.4.3)