Update mbed-coap to version 4.7.0

[anttiylitokola]

Description

• Add function that can be used to clear the received blockwise payloads for example in the case of a connection error.
• Silence compiler warning when CoAP duplicate detection is enabled.

Pull request type

[X] Fix
[ ] Refactor
[ ] Target update
[ ] Functionality change
[ ] Breaking change

[anttiylitokola]

@yogpan01, please review.

[yogpan01]

Approved. This is needed for client to handle memory gracefully when it is recovering from connection break while in the middle of firmware download.

[0xc0170]

/morph build

[mbed-ci]

Build : SUCCESS

Build number : 3215
Build artifacts/logs : http://mbed-os.s3-website-eu-west-1.amazonaws.com/?prefix=builds/8273/

Triggering tests

/morph test
/morph mbed2-build

[mbed-ci]

Test : FAILURE

Build number : 3017
Test logs :http://mbed-os-logs.s3-website-us-west-1.amazonaws.com/?prefix=logs/8273/3017

[0xc0170]

/morph test

[mbed-ci]

Test : FAILURE

Build number : 3032
Test logs :http://mbed-os-logs.s3-website-us-west-1.amazonaws.com/?prefix=logs/8273/3032

[0xc0170]

/morph test
/morph export-build

[mbed-ci]

Exporter Build : SUCCESS

Build number : 2846
Build artifacts/logs : http://mbed-os.s3-website-eu-west-1.amazonaws.com/?prefix=builds/exporter/8273/

[mbed-ci]

Test : SUCCESS

Build number : 3064
Test logs :http://mbed-os-logs.s3-website-us-west-1.amazonaws.com/?prefix=logs/8273/3064

[cmonr]

@ChiefBureaucraticOfficer Could you take a look at this?

A new function was added, but it appears that this might be needed in a patch release for cloud client (correct @yogpan01?).

[ghost]

@ChiefBureaucraticOfficer Could you take a look at this?

A new function was added, but it appears that this might be needed in a patch release for cloud client (correct @yogpan01?).

Please clarify - has the owner of COAP reviewed these changes? The changes are optional, no adoption is required by existing users? No other known behaviors are altered?

If the answers to all of the above are 'yes', then the process excursion is APPROVED for the PR.

[yogpan01]

@0xc0170 @ChiefBureaucraticOfficer
CoAP changes are feature enhancement and are completely optional. Existing users of CoAP may or may not use it and it will not impact to any existing functionality of CoAP library.
Since, its a complete new API there is no changed behaviour in any of the existing source code or APIs.