[PATCH] Upgrade to buildbot 3.6.1

[Mark Wielaard <mark@klomp.org>]

This includes our patch for:
- Fixed issue with DockerLatentWorker accumulating connections with
  the docker server (issue #6538).

It will hopefully also fix our git upgrade failure issue:
- Fixed “retry fetch” and “clobber on failure” git checkout options.

Include upgrade instructions in README.
---
 README                | 12 ++++++++++++
 buildbot.requirements | 12 ++++++------
 2 files changed, 18 insertions(+), 6 deletions(-)

diff --git a/README b/README
index 93ab54e..b909026 100644
--- a/README
+++ b/README
@@ -229,6 +229,18 @@ If this seems to not work check whether there are still git
 change-sources being checked and wait till they have done their
 work.
 
+= Upgrading buildbot
+
+Try this locally first.
+
+- python3 -m pip install --upgrade `cat buildbot.packages`
+- python3 -m pip freeze > buildbot.requirements
+
+Try the new setup first as under "Local hacking".
+
+After check in someone with buildbot shell access will have to
+actually stop, upgrade and restart the buildbot on sourceware.
+
 = Reconfig buildbot
 
 When making any changes to master.cfg. Please test everything first in
diff --git a/buildbot.requirements b/buildbot.requirements
index f62ee80..2e294e6 100644
--- a/buildbot.requirements
+++ b/buildbot.requirements
@@ -3,11 +3,11 @@ attrs==21.4.0
 autobahn==21.2.1
 Automat==20.2.0
 bcrypt==3.2.0
-buildbot==3.5.0
-buildbot-badges==3.5.0
-buildbot-console-view==3.5.0
-buildbot-worker==3.5.0
-buildbot-www==3.5.0
+buildbot==3.6.1
+buildbot-badges==3.6.1
+buildbot-console-view==3.6.1
+buildbot-worker==3.6.1
+buildbot-www==3.6.1
 cairocffi==1.2.0
 CairoSVG==2.5.2
 certifi==2021.10.8
@@ -32,7 +32,7 @@ klein==21.8.0
 Mako==1.1.6
 MarkupSafe==2.0.1
 msgpack==1.0.3
-paramiko==2.10.3
+paramiko==2.11.0
 Pillow==8.4.0
 pyasn1==0.4.8
 pyasn1-modules==0.2.8
-- 
2.30.2