`#shush_backtraces` doesn't clean the `backtrace_locations`

[amomchilov]

The Spring::Application#shush_backtraces method strips out Spring stackframes from the exception's backtrace, but not its backtrace_locations:

spring/lib/spring/application.rb

Line 322 in 046d50a

$!.backtrace.reject! { |line| line.start_with?(lib) } unless $!.backtrace.frozen?

This causes at least 2 issues:

1. The backtrace and backtrace_locations become out of sync, and only when running in Spring.
2. It breaks the downstream behaviour of ActiveSupport::ErrorReporter, whose #report method will clean itself off the top of the stack. Since the top of the stack will be these 2 Spring frames, its logic won't remove any of the frames.

Example

#!/opt/rubies/3.4.2/bin/ruby

begin
 raise
rescue => e
end

puts "\nbacktrace:"
puts e.backtrace.first(2)

puts "\nbacktrace_locations:"
puts e.backtrace_locations.first(4)

Output (truncated):

$ bundle exec rails runner demo.rb
Running via Spring preloader in process 33573
running spring after_fork

backtrace
.../demo.rb:4:in '<main>'
.../gems/rails-8b00d0985f88/railties/lib/rails/commands/runner/runner_command.rb:44:in 'Kernel.load'

backtrace_locations
.../gems/spring-4.2.1/lib/spring/application.rb:313:in 'Method#call'
.../gems/spring-4.2.1/lib/spring/application.rb:313:in 'block (2 levels) in Kernel#shush_backtraces'
.../demo.rb:4:in '<main>'
.../gems/rails-8b00d0985f88/railties/lib/rails/commands/runner/runner_command.rb:44:in 'Kernel.load'