Clean up project export error logging

Right now when an exception happens, two messages are logged: one with a
basic debug message, and another with the full error backtrace.  We can
clean this up by emitting one error message with a cleaned backtrace as
an array.

lib/gitlab/import_export/shared.rb

@@ -56,8 +56,9 @@ module Gitlab
       end
 
       def error(error)
-        log_error(message: error.message, caller: caller[0].dup)
-        log_debug(backtrace: error.backtrace&.join("\n"))
+        error_payload = { message: error.message }
+        error_payload[:error_backtrace] = Gitlab::Profiler.clean_backtrace(error.backtrace) if error.backtrace
+        log_error(error_payload)
 
         Gitlab::Sentry.track_acceptable_exception(error, extra: log_base_data)
 

spec/lib/gitlab/import_export/shared_spec.rb

@@ -53,16 +53,17 @@ describe Gitlab::ImportExport::Shared do
       subject.error(error)
     end
 
-    it 'calls the error logger with the full message' do
-      expect(subject).to receive(:log_error).with(hash_including(message: error.message))
+    it 'calls the error logger without a backtrace' do
+      expect(subject).to receive(:log_error).with(message: error.message)
 
       subject.error(error)
     end
 
-    it 'calls the debug logger with a backtrace' do
-      error.set_backtrace('backtrace')
+    it 'calls the error logger with the full message' do
+      backtrace = caller
+      allow(error).to receive(:backtrace).and_return(caller)
 
-      expect(subject).to receive(:log_debug).with(hash_including(backtrace: 'backtrace'))
+      expect(subject).to receive(:log_error).with(message: error.message, error_backtrace: Gitlab::Profiler.clean_backtrace(backtrace))
 
       subject.error(error)
     end