images: Pin python protobuf version and change salt repo URL

[TeddyAndrieux]

Fix the build of salt-master and metalk8s-utils images

• etcd3 python lib require protobuf>=3.6.1 python lib and the latest protobuf version is not compatible with python3.6

# pip3 install etcd3
Collecting etcd3
  Using cached etcd3-0.12.0.tar.gz (63 kB)
Collecting grpcio>=1.27.1
  Downloading grpcio-1.46.3-cp36-cp36m-manylinux_2_17_x86_64.manylinux2014_x86_64.whl (4.4 MB)
     |████████████████████████████████| 4.4 MB 14.0 MB/s 
Collecting protobuf>=3.6.1
  Downloading protobuf-4.21.0-py2.py3-none-any.whl (164 kB)
     |████████████████████████████████| 164 kB 65.9 MB/s 
ERROR: Package 'protobuf' requires a different Python: 3.6.8 not in '>=3.7'

• Salt master repo URL moved and yum does not handle redirect

failure: repodata/repomd.xml from saltstack-repo: [Errno 256] No more mirrors to try.
https://repo.saltstack.com/py3/redhat/7/x86_64/archive/3002.8/repodata/repomd.xml: [Errno 14] HTTPS Error 301 - Moved Permanently

[bert-e]

Hello teddyandrieux,

My role is to assist you with the merge of this
pull request. Please type @bert-e help to get information
on this process, or consult the user documentation.

Status report is not available.

[bert-e]

Integration data created

I have created the integration data for the additional destination branches.

• this pull request will merge bugfix/fix-salt-master-build into
  development/2.11
• w/123.0/bugfix/fix-salt-master-build will be merged into development/123.0

The following branches will NOT be impacted:

• development/2.0
• development/2.1
• development/2.10
• development/2.2
• development/2.3
• development/2.4
• development/2.5
• development/2.6
• development/2.7
• development/2.8
• development/2.9

You can set option create_pull_requests if you need me to create
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[bert-e]

Waiting for approval

The following approvals are needed before I can proceed with the merge:

• the author

• one peer

Peer approvals must include at least 1 approval from the following list:

• @alexandre-allard-scality

• @JBWatenbergScality

• @NicolasT

• @gdemonet

• @TeddyAndrieux

• @thomasdanan

• @lucieleonard

• @ChengYanJin

[TeddyAndrieux]

/approve

[bert-e]

In the queue

The changeset has received all authorizations and has been added to the
relevant queue(s). The queue(s) will be merged in the target development
branch(es) as soon as builds have passed.

The changeset will be merged in:

• ✔️ development/2.11

• ✔️ development/123.0

The following branches will NOT be impacted:

• development/2.0
• development/2.1
• development/2.10
• development/2.2
• development/2.3
• development/2.4
• development/2.5
• development/2.6
• development/2.7
• development/2.8
• development/2.9

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If you need this pull request to be removed from the queue, please contact a
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The following options are set: approve

[bert-e]

I have successfully merged the changeset of this pull request
into targetted development branches:

• ✔️ development/2.11

• ✔️ development/123.0

The following branches have NOT changed:

• development/2.0
• development/2.1
• development/2.10
• development/2.2
• development/2.3
• development/2.4
• development/2.5
• development/2.6
• development/2.7
• development/2.8
• development/2.9

Please check the status of the associated issue None.

Goodbye teddyandrieux.