Handle reader macros when merging EDN files

[hlship]

• Please check if the PR fulfills these requirements

• [ x] There is an open issue describing the problem that this pr intents to solve.
  • [ x] You have a descriptive commit message with a short title (first line).
• [ x] Tests for the changes have been added (for bug fixes / features).
• [ x] Docs have been added / updated (for bug fixes / features).

• What kind of change does this PR introduce? (Bug fix, feature, docs update, ...)

• What is the current behavior?

The tool throws an exception when attempting to merge EDN files containing undefined reader macros.

• What is the new behavior (if this is a feature change)?

The EDN files are merged, and reader macros are maintained (via clojure.core/tagged-literal).

• Does this PR introduce a breaking change? (What changes might users need to make in their application due to this PR?)

No.

[hlship]

I don't know why the workflow bits are failing, I bumped the versions to no avail.