[Security] Bump django from 2.1.11 to 2.1.15

[dependabot-preview]

Bumps django from 2.1.11 to 2.1.15. This update includes a security fix.

Vulnerabilities fixed

Sourced from The GitHub Security Advisory Database.

Moderate severity vulnerability that affects django Django 2.1 before 2.1.15 and 2.2 before 2.2.8 allows unintended model editing. A Django model admin displaying inline related models, where the user has view-only permissions to a parent model but edit permissions to the inline model, would be presented with an editing UI, allowing POST requests, for updating the inline model. Directly editing the view-only parent model was not possible, but the parent model's save() method was called, triggering potential side effects, and causing pre and post-save signal handlers to be invoked. (To resolve this, the Django admin is adjusted to require edit permissions on the parent model in order for inline models to be editable.)

Affected versions: >= 2.1.0, < 2.1.15

Commits

• 3baf68b [2.1.x] Bumped version for 2.1.5 release.
• 2fc998e [2.1.x] Added release date for 2.1.15.
• 103ebe2 Fixed CVE-2019-19118 -- Required edit permissions on parent model for editabl...
• f57f81a [2.1.x] Refs #30953 -- Added 2.1.15 release note for 0107e3d1058f653f66032f7f...
• 015fab7 [2.1.x] Fixed #30953 -- Made select_for_update() lock queryset's model when u...
• ed50f6c [2.1.x] Made versionadded/versionchanged annotations without a content end wi...
• 0423ea1 [2.1.x] Added stub release notes for 2.1.15.
• cfc0378 [2.1.x] Post-release version bump.
• 11f29b6 [2.1.x] Bumped version for 2.1.14 release.
• 341b2aa [2.1.x] Added release dates for 2.1.14 and 1.11.26.
• Additional commits viewable in compare view

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