requirements: Explicitly specefy phonenumberslite as a dependency.

If we don't specify phonenumberslite explicitly it would
be removed when setuptools is upgraded to latest version.

requirements/common.in

@@ -193,6 +193,13 @@ lxml==4.3.3
 
 # Needed for 2-factor authentication
 django-two-factor-auth==1.8.0
+
+# Required by django-phonenumber-field which is a dependency of django-two-factor-auth.
+# Developers can install either phonenumberslite or phonenumbers. Developers of
+# django-two-factor-auth has not specified which package to install so we are going
+# with phonenumberslite since it has less memory footprint.
+phonenumberslite==8.10.12
+
 twilio==6.26.2
 
 # Needed for processing payments (in corporate)

requirements/dev.txt

@@ -108,7 +108,7 @@ parsel==1.5.1             # via scrapy
 parso==0.4.0              # via jedi
 pbr==5.1.3                # via mock
 pexpect==4.7.0            # via ipython
-phonenumberslite==8.10.10  # via django-phonenumber-field
+phonenumberslite==8.10.12
 pickleshare==0.7.5        # via ipython
 pika==0.13.0
 pillow==5.4.1

requirements/prod.txt

@@ -78,7 +78,7 @@ oauthlib==3.0.1
 parso==0.4.0              # via jedi
 pbr==5.1.3                # via mock
 pexpect==4.7.0            # via ipython
-phonenumberslite==8.10.10  # via django-phonenumber-field
+phonenumberslite==8.10.12
 pickleshare==0.7.5        # via ipython
 pika==0.13.0
 pillow==5.4.1