The operator to specify the version of joblib is invalid

[c-bata]

What does this PR do?

The operator to specify the version of joblib is invalid.

$ python3.7 -m venv venv
$ source venv/bin/activate
(venv) $ pip install -r requirements.txt
Invalid requirement: 'joblib=0.10.3'
= is not a valid operator. Did you mean == ?

Where should the reviewer start?

How should this PR be tested?

Please execute pip install -r requirements.txt

Any background context you want to provide?

nothing

What are the relevant issues?

nothing

Screenshots (if appropriate)

no needed

Questions:

• Do the docs need to be updated? no
• Does this PR add new (Python) dependencies? no

[weixuanfu]

Good catch! Thank you for the PR.