[Security] Bump log4net from 2.0.8 to 2.0.12

[dependabot-preview[bot]]

Bumps log4net from 2.0.8 to 2.0.12.

Release notes

Sourced from log4net's releases.

Fixes LOG4NET-(652|653)

Should resolve issues with PlatformNotSupported exceptions raised on !win32 when attempting to include the current user name in logs.

Correct assembly versions

• corrects assembly versioning still reported as 2.0.9 in the 2.0.10 release
• ensures that stream writers used during log flushing are properly disposed
• corrects version strings for client profile assemblies

Address CVE-2018-1285 and improve netstandard 2.0 support

Apache log4net 2.0.10 improves netstandard2.0 support thanks to community member @NicholasNoise.

Bug Fixes

• [LOG4NET-575] Addresses CVE-2018-1285 by cherry-picking the fix from Dominik Psenner, reported by Karthik Balasundaram, as it already existed in the the develop branch

Commits

• 47aaf46 :bookmark: bump version to 2.0.12, fixes LOG4NET-(652|653)
• bf81ef2 :bookmark: update versioning to 2.0.12.0
• e137855 :bug: should fall back on Environment.UserName if !win32
• 141b00b :tada: build-xplatform works; now to get tests running...
• 9e3b1d1 :memo: add documentation about building with docker
• 31c577e :ambulance: retroactively fix up site source doap file
• fa0cd5b :construction: let's get this building a subset x-platform so we can test x-p...
• 1a1f9fa :bug: should not fail when platform does not support fetching windows user name
• 525526b :art: sort modifiers with default .net style sorting
• d5cb207 :memo: add documentation about proposed 2.0.11 release
• Additional commits viewable in compare view

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[dependabot-preview[bot]]

We've just been alerted that this update fixes a security vulnerability:

Sourced from The GitHub Security Advisory Database.

XML External Entity attack in log4net

Apache log4net before 2.0.10 does not disable XML external entities when parsing log4net configuration files. This could allow for XXE-based attacks in applications that accept arbitrary configuration files from users.

Affected versions: ["< 2.0.10"]