[typescript-angular] Fix undefined query param when queryParamObjectFormat=json

[djnalluri]

Fixes #7619

Attempting to pass an object as a query parameter while queryParamObjectFormat=json currently results in the key being set to undefined. This PR ensures the key is always provided when the JSON object format is used.

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Technical Committee
@TiFu (2017/07) @taxpon (2017/07) @sebastianhaas (2017/07) @kenisteward (2017/07) @Vrolijkx (2017/09) @macjohnny (2018/01) @topce (2018/10) @akehir (2019/07) @petejohansonxo (2019/11) @amakhrov (2020/02)

[macjohnny]

LGTM

[Traksewt]

@macjohnny Is this bug fix getting backported to a new 5.1.2, as I cannot see how to install 5.2 pre-release from the cli? Waiting for this fix.thx

[macjohnny]

The fix is not backported, but you can download the snapshot JAR