Upstream apparmor fix at
https://gitlab.com/apparmor/apparmor/-/merge_requests/1819. I intend to
SRU this fix in as a bundle along with other AppArmor fixes.

** Description changed:

+ [ Impact ]
+ 
+ tnftp is unable to access the ~/.netrc configuration file, which it uses
+ in order to load login information and automatically login to FTP
+ servers as stored in the config. Without this config, automatic login
+ functionality is broken.
+ 
+ [ Test Plan ]
+ 
+ On a (Plucky|Questing|Resolute) machine,
+ - Install tnftp, if it isn't installed already
+ - Create a ~/.netrc file and populate it with the line "default login 
anonymous password user@site".
+ - Attempt to download a file using FTP, e.g. `tnftp 
ftp://mirror.us.leaseweb.net/ubuntu-releases/robots.txt`
+ - Without the patch: tnftp is unable to read ~/.netrc and generates a 
permission denial error
+ - With the patch: tnftp is able to read and use ~/.netrc
+ 
+ [ Where problems could occur ]
+ 
+ The additions to the tnftp profile are loosening confinement. However,
+ if a user manually modified the installed profiles, then the package
+ upgrade would cause conflicts, and rejection of the incoming changes
+ (either by hand during an interactive upgrade or automatically during an
+ batch unattended upgrade) would result in end users not getting the
+ packaged fix.
+ 
+ [ Other Info ]
+ 
+ -------Original report:
+ 
  Version of Ubuntu: 25.04
  Version of tnftp: 20230507-2build3
  
  What is expected to happen:
  FTP credentials are put in the file $HOME/.netrc with permissions 600, and 
are read by tnftp to log in to the remote server.
  
  What happens:
  On starting tnftp it attempts to open the file $HOME/.netrc which fails with 
the following error message:
  ftp: Can't read `.netrc': Permission denied
  
  Origin of the bug:
  I tracked it down to the default AppArmor policy in 
/etc/apparmor.d/abstractions/private-files and specifically the block:
-   # don't allow reading/updating of run control files
-   deny @{HOME}/.*rc mrk,
+   # don't allow reading/updating of run control files
+   deny @{HOME}/.*rc mrk,
  
  Proposed bug fix:
  Add the following line to the tnftp AppArmor policy:
-   priority=100 allow owner @{HOME}/.netrc r,
+   priority=100 allow owner @{HOME}/.netrc r,
  
  The priority=100 is necessary because `deny` executes after `allow`.

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https://bugs.launchpad.net/bugs/2127491

Title:
  AppArmor policy prevents reading from $HOME/.netrc

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