Fix deprecated warning using mongodb extension 1.20 or greater in ReadPrederence::getMode()

[Vegeeto]

Steps to reproduce:

1. Add the following option to makefile

.PHONY: setup-74-mongo-5
setup-74-mongo-5: PHP_VERSION=7.4
setup-74-mongo-5: MONGODB_EXTENSION_VERSION=1.20.0
setup-74-mongo-5: MONGODB_VERSION=5.0
setup-74-mongo-5: | --build --setup-common

2. Enter to the container: make sh
3. Execute unit tests: make tests

Added a mongodb version check in order to use getModeString() method instead of calling getMode()
Added tests to check

PS: I don't like so much the way I tested it. If you have any suggestion, please feel free to comment it. Thanks!

Resolves #185 #185

[ilario-pierbattista]

PS: I don't like so much the way I tested it. If you have any suggestion, please feel free to comment it. Thanks!

hey @Vegeeto, why don't you add an item with that configuration here? https://github.com/facile-it/mongodb-bundle/blob/master/.github/workflows/ci.yaml#L29

[ilario-pierbattista]

thank you @Vegeeto, released in https://github.com/facile-it/mongodb-bundle/releases/tag/1.6.1