test(e2e): Add database migration test (#2627)

* test(e2e): Add database migration test

* chore(enos): Add enos scenario for migration test

* chore(enos): Update go test command to use count option

* doc(e2e): Update readme with migration test details

* Fix: Typo

* CR: Use different library

* CR: Add additional context in comment

* CR: Move some code from test into functions

* doc(e2e): Add instructions to more easily retrieve environment variables

* refact(e2e): Create some more methods to increase test readability

testing/internal/e2e/tests/database/testdata/postgresql.conf

@@ -0,0 +1,14 @@
+listen_addresses           = '*'
+max_connections            = 100
+work_mem                   = 50000kB
+shared_buffers             = 64MB
+log_destination            = 'stderr'
+deadlock_timeout           = 100
+log_min_messages           = info
+log_min_error_statement    = error
+log_error_verbosity        = verbose
+log_lock_waits             = true
+log_statement              = all
+log_duration               = on
+log_min_duration_statement = 0
+log_line_prefix            = '%m [%p] (%x) %i '