Replace factory_girl_rails with factory_bot_railsrc/use-factory_bot_rails

I've followed the [upgrade guide](https://github.com/thoughtbot/factory_bot/blob/4-9-0-stable/UPGRADE_FROM_FACTORY_GIRL.md) and ran these two commands:

```
grep -e FactoryGirl **/*.rake **/*.rb -s -l | xargs sed -i "" "s|FactoryGirl|FactoryBot|"
grep -e factory_girl **/*.rake **/*.rb -s -l | xargs sed -i "" "s|factory_girl|factory_bot|"
```

Signed-off-by: Rémy Coutable <remy@rymai.me>

1 files changed, 2 insertions, 2 deletions

diff --git a/doc/development/gotchas.md b/doc/development/gotchas.md
index c2ca8966a3f..5786287d00c 100644
--- a/doc/development/gotchas.md
+++ b/doc/development/gotchas.md
@@ -8,7 +8,7 @@ might encounter or should avoid during development of GitLab CE and EE.
 Consider the following factory:
 
 ```ruby
-FactoryGirl.define do
+FactoryBot.define do
   factory :label do
     sequence(:title) { |n| "label#{n}" }
   end
@@ -53,7 +53,7 @@ When run, this spec doesn't do what we might expect:
      (compared using ==)
 ```
 
-That's because FactoryGirl sequences are not reseted for each example.
+That's because FactoryBot sequences are not reseted for each example.
 
 Please remember that sequence-generated values exist only to avoid having to
 explicitly set attributes that have a uniqueness constraint when using a factory.