Remove asserts from static functions

[kar-rahul-aws]

Description

This PR removes unnecessary asserts from static functions. The NULL check for the pointer variables are unnecessary , since these are static functions and non-NULL values are always passed from the caller functions. As a result, the code coverage increases.

Test Steps

make -C build/ coverage
declare -a EXCLUDE=("\*test\*" "\*CMakeCCompilerId\*" "\*mocks\*" "\*vendor/unity\*" "\*_deps\*")
echo ${EXCLUDE[@]} | xargs lcov --rc lcov_branch_coverage=1 -r build/coverage.info -o build/coverage.info
lcov --rc lcov_branch_coverage=1 --list build/coverage.info

Before patch

                                   |Lines       |Functions  |Branches    
Filename                           |Rate     Num|Rate    Num|Rate     Num
=========================================================================
[/home/ubuntu/Temp/karahulx_coreMQTTFileStreams/aws-iot-core-mqtt-file-streams-embedded-c/source/]
MQTTFileDownloader.c               |97.3%    146| 100%     9|96.0%    100
MQTTFileDownloader_base64.c        |99.0%    103| 100%     4|85.2%     88
MQTTFileDownloader_cbor.c          | 100%     85| 100%     3| 100%     88
=========================================================================
                             Total:|98.5%    334| 100%    16|93.8%    276

After patch

                                   |Lines       |Functions  |Branches    
Filename                           |Rate     Num|Rate    Num|Rate     Num
=========================================================================
[/home/ubuntu/Temp/karahulx_coreMQTTFileStreams/aws-iot-core-mqtt-file-streams-embedded-c/source/]
MQTTFileDownloader.c               |97.3%    146| 100%     9|96.0%    100
MQTTFileDownloader_base64.c        |98.9%     95| 100%     4|93.1%     72
MQTTFileDownloader_cbor.c          | 100%     85| 100%     3| 100%     88
=========================================================================
                             Total:|98.5%    326| 100%    16|96.5%    260

Checklist:

• I have tested my changes. No regression in existing tests.
• I have modified and/or added unit-tests to cover the code changes in this Pull Request.

Related Issue

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