add nodejs16 as runtime

[networkandcode]

What did you implement:

Added support for node16 and removed node10,, similar to this change https://github.com/serverless/serverless-azure-functions/pull/537/commits
Closes #XXXXX

I saw this issue when I tried deplpying with nodejs16 runtime.

Error:
Error: Runtime nodejs16 is not supported. Runtimes supported: nodejs10,nodejs12,nodejs14,python3.6,python3.7,python3.8,dotnet2.2,dotnet3.1
    at ConfigService.initializeConfig (/home/g115386/notifications/node_modules/serverless-azure-functions/lib/services/configService.js:195:19)
    at new ConfigService (/home/g115386/notifications/node_modules/serverless-azure-functions/lib/services/configService.js:26:28)
    at new AzurePackagePlugin (/home/g115386/notifications/node_modules/serverless-azure-functions/lib/plugins/package/azurePackagePlugin.js:67:29)

How did you implement it:

Changed src/config/runtime, src/config/runtime.test.ts, src/services/configService.test.ts and readme

How can we verify it:

Todos:

Note: Run npm run test:ci to run all validation checks on proposed changes

• Ensure there are no lint errors.
  Validate via npm run lint
  Note: Some reported issues can be automatically fixed by running npm run lint:fix
• Write tests and confirm existing functionality is not broken.
  Validate via npm test
• Write documentation
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• Enable "Allow edits from maintainers" for this PR
• Update the messages below

Is this ready for review?: NO
Is it a breaking change?: NO

[mcremer-able]

Dont you also need to upgrade the azure-function-core-tools dependency to V4 to use Node16 ?

[kevboutin]

Dont you also need to upgrade the azure-function-core-tools dependency to V4 to use Node16 ?

No, the latest azure-function-core-tools is installed as per instructions in the README. You are probably getting confused with the functionApp->extensionVersion in the serverless.yml file.

[gligorkot]

This was completed with #640 feel free to use release 2.2.1 for node 16 and 18 support https://github.com/serverless/serverless-azure-functions/releases/tag/v2.2.1