No need to run uberjar via babashka.process/exec

[jeroenvandijk]

bbin install <uberjar> will create a wrapper script that relies on babashka.process/exec to execute the jar. This means that babashka is invoked twice, adding extra startup time for the script (also see #45).

After some personal testing and a conversation with @borkdude in Slack I believe this is unnecessary.

Proposed alternative

• The wrapper script would need to be adapted to something like:

(require '[babashka.classpath :refer [add-classpath]])
(add-classpath "the-uber-jar.jar")
(require '[the-main-ns])
(apply the-main-ns/-main *command-line-args*)

• The install process has to find the main class, and fail if it cannot find the main-ns (and maybe also when it cannot find a -main in that namespace).

I've played around with the compiled code from Babashka itself to find the main ns and I found that this runs in interpreted Babashka as well. (here and here)

I'll create a PR for this issue somewhere the coming days unless there are reasons for babashka.process/exec that I missed.