Fix silently broken test_version.sh tests

[mbland]

Description

Fixes silently broken tests depending on test_version/test_reporter and adds an assertion to avoid future silent breakages. Part of #1482 and #1652.

• Moves test_version/version_specific_tests_dir/scala_repositories.bzl to test_version.

• Updates test_version.sh to copy this file into test repos generated from both version_specific_tests_dir and test_reporter.

• Updates compilation_should_fail to break if the bazel build output doesn't contain the expected ErrorFile.scala error.

Motivation

The affected test cases expect their underlying builds to fail because of errors in test_version/test_reporter/ErrorFile.scala. Failing Scala 2.x build output should contain:

ErrorFile.scala:6: ')' expected but '}' found

Failing Scala 3.x build output should contain:

-- [E040] Syntax Error: ErrorFile.scala:6:2 ------------------------------------
6 |  }
  |  ^
  |  ')' expected, but '}' found

Using RULES_SCALA_TEST_ONLY to select an affected test case revealed that the underlying build actually failed because Bazel couldn't find //:scrooge_repositories.bzl:

$ RULES_SCALA_TEST_ONLY="test_reporter 2.12.20 //:diagnostics_reporter_toolchain" \
  ./test_version.sh

running test test_reporter 2.12.20 //:diagnostics_reporter_toolchain
Starting local Bazel server and connecting to it...
Computing main repo mapping:
ERROR: Error computing the main repository mapping:
  cannot load '//:scrooge_repositories.bzl': no such file

$ echo $?

0