[misc] fix install_deps

[das7pad]

Description

The version of aspell-ta was bumped again, which broke the builds. aspell-or and aspell-no were bumped as well.

This time I am proposing to use any latest version that is available.

I added a policy and pinned the release for the aspell-* packages to unstable. The priority must be larger than the APT::Default-Release priority of 990. This applies to the second batch of package installations only.

Screenshots

``` # in a node:10.19.0 container will all steps from install_deps.sh # executed -- except for the 'apt install' steps. $ apt policy aspell-or aspell-te aspell-no aspell-ta aspell-or: Installed: (none) Candidate: 0.03-1-7 Version table: 0.03-1-7 1337 500 http://deb.debian.org/debian unstable/main ... 0.03-1-5 990 990 http://deb.debian.org/debian stretch/main ... 0.03-1-5 500 500 http://archive.ubuntu.com/ubuntu bionic/universe ... aspell-te: Installed: (none) Candidate: 0.01-2-7 Version table: 0.01-2-7 1337 500 http://deb.debian.org/debian unstable/main ... 0.01-2-5 990 990 http://deb.debian.org/debian stretch/main ... 0.01-2-5 500 500 http://archive.ubuntu.com/ubuntu bionic/universe ... aspell-no: Installed: (none) Candidate: 2.2-4 Version table: 2.2-4 1337 500 http://deb.debian.org/debian unstable/main ... 2.2-3 500 500 http://archive.ubuntu.com/ubuntu bionic/universe ... 2.2-2 990 990 http://deb.debian.org/debian stretch/main ... aspell-ta: Installed: (none) Candidate: 20040424-1-3 Version table: 20040424-1-3 1337 500 http://deb.debian.org/debian unstable/main ... 20040424-1-1 990 990 http://deb.debian.org/debian stretch/main ... 20040424-1-1 500 500 http://archive.ubuntu.com/ubuntu bionic/universe ... ```

Related Issues / PRs

https://github.com/overleaf/spelling/pull/55 https://github.com/overleaf/spelling/pull/54 https://github.com/overleaf/spelling/pull/16

Review

To speed up local builds I switched from the us mirrors to the respective mirror redirectors.

[mans0954]

Yes, apt-pinning a better solution.