Upgrades to containerd, fix deprecations upstream

* Fixes upstream deprecations for containerd
* Fixes deprecations in ioutil package usage
* Break out separate files for function handlers
* Upgrades containerd to 1.7.22
* Fixes default namespace functionality
* Pre-deploy checks as per license agreement
* Removes extra log messages for payload in HTTP handlers, you
can enable FAAS_DEBUG=1 in the CLI instead to see this from
the client's perspective
* Add additional Google DNS server 8.8.4.4 for functions

Signed-off-by: Alex Ellis (OpenFaaS Ltd) <alexellis2@gmail.com>

vendor/github.com/containerd/platforms/defaults.go

@@ -0,0 +1,29 @@
+/*
+   Copyright The containerd Authors.
+
+   Licensed under the Apache License, Version 2.0 (the "License");
+   you may not use this file except in compliance with the License.
+   You may obtain a copy of the License at
+
+       http://www.apache.org/licenses/LICENSE-2.0
+
+   Unless required by applicable law or agreed to in writing, software
+   distributed under the License is distributed on an "AS IS" BASIS,
+   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+   See the License for the specific language governing permissions and
+   limitations under the License.
+*/
+
+package platforms
+
+// DefaultString returns the default string specifier for the platform,
+// with [PR#6](https://github.com/containerd/platforms/pull/6) the result
+// may now also include the OSVersion from the provided platform specification.
+func DefaultString() string {
+	return FormatAll(DefaultSpec())
+}
+
+// DefaultStrict returns strict form of Default.
+func DefaultStrict() MatchComparer {
+	return OnlyStrict(DefaultSpec())
+}