Update broken sbt Debian repo in Scala template

What does this MR do and why?

Update the broken sbt Debian repo being used in the Scala template. This was updated according to the info available in the official sbt documentation: https://www.scala-sbt.org/1.x/docs/Installing-sbt-on-Linux.html#Ubuntu+and+other+Debian-based+distributions

Screenshots or screen recordings

$ apt-get update -yqq
E: Failed to fetch http://dl.bintray.com/sbt/debian/InRelease  403  Forbidden [IP: 52.34.245.248 80]
E: The repository 'http://dl.bintray.com/sbt/debian  InRelease' is not signed.
Cleaning up project directory and file based variables
00:01
ERROR: Job failed: exit code 1

How to set up and validate locally

$ apt-get install sbt -yqq
debconf: delaying package configuration, since apt-utils is not installed
Selecting previously unselected package sbt.
(Reading database ... 12680 files and directories currently installed.)
Preparing to unpack .../apt/archives/sbt_1.4.9_all.deb ...
Unpacking sbt (1.4.9) ...
Setting up sbt (1.4.9) ...
Creating system group: sbt
Creating system user: sbt in sbt with sbt daemon-user and shell /bin/false
$ sbt sbtVersion

MR acceptance checklist

This checklist encourages us to confirm any changes have been analyzed to reduce risks in quality, performance, reliability, security, and maintainability.

• I have evaluated the MR acceptance checklist for this MR.