Revert "Temporary disable upgrade path from 7 to 8.10"

This reverts commit 59dfd37.

Author: yuravk

repos/system_upgrade/common/files/upgrade_paths.json

@@ -1,9 +1,9 @@
 {
     "default": {
-        "7.9": ["8.7", "8.8", "8.9"],
+        "7.9": ["8.7", "8.8", "8.9", "8.10"],
         "8.10": ["9.0", "9.1", "9.2", "9.3", "9.4", "9.5"],
         "9.6": ["10.0"],
-        "7": ["8.7", "8.8", "8.9"],
+        "7": ["8.7", "8.8", "8.9", "8.10"],
         "8": ["9.0", "9.1", "9.2", "9.3", "9.4", "9.5"],
         "9": ["10.0"]
     },