Fix sporadic test failure

[Fryguy]

If the cli_spec.rb's set_replication specs ran on macOS before database_replication_standby_spec.rb's register_standby_server specs, the former would create a $CHILD_STATUS var with a failing result. Then when the register_standby_server spec would run it stubs the forking call, but doesn't stub $CHILD_STATUS, resulting in a call to $CHILD_STATUS.success? which would return false.

While we could change the test to also stub $CHILD_STATUS.success? to return true, this only works on Ruby 2.7. On Ruby 3.0 this fails with a modify frozen object error.

Instead, what we can do is use Process.wait2 instead of Process.wait+$CHILD_STATUS.success? This way, we can stub the status object as well.

@agrare Please review.

The following is an example seed that failed for me:

SPEC_OPTS="--seed 4884" bundle exec rspec spec/database_replication_standby_spec.rb:195 spec/cli_spec.rb:702

[Fryguy]

Note that running the specs with 3.0 produces a lot of errors, but they are unrelated to this specific error.

[agrare]

$ SPEC_OPTS="--seed 4884" bundle exec rspec spec/database_replication_standby_spec.rb:195 spec/cli_spec.rb:702
Run options: include {:locations=>{"./spec/database_replication_standby_spec.rb"=>[195], "./spec/cli_spec.rb"=>[702]}}

Randomized with seed 4884

ManageIQ::ApplianceConsole::Cli
  #set_replication
Configuring Server as Primary
    should configure DB as primary when the required arguments are specified
Configuring Server as Primary
    should configure primary replication with a fixed database name and user when specified in the flags
Configuring Server as Standby
    should configure DDBB replication as standby when the required parameters are specified
Configuring Server as Standby
    should configure repmgrd when auto-failover flag is set

ManageIQ::ApplianceConsole::DatabaseReplicationStandby
  create standby server
    #register_standby_server
      Succeed when REGISTER_CMD succeeds

Finished in 0.01988 seconds (files took 0.36837 seconds to load)
5 examples, 0 failures

Randomized with seed 4884

[miq-bot]

Checked commit Fryguy@2e404e7 with ruby 2.6.10, rubocop 1.28.2, haml-lint 0.35.0, and yamllint
3 files checked, 2 offenses detected

lib/manageiq/appliance_console/database_replication.rb

• ⚠️ - Line 154, Col 7 - Lint/UselessAssignment - Useless assignment to variable - pid. Use _ or _pid as a variable name to indicate that it won't be used.

spec/cli_spec.rb

• ❗ - Line 707, Col 81 - Performance/StringInclude - Use String#include? instead of a regex match with literal-only pattern.