Bump minimum PHP support to 7.4

[ernilambar]

Fixes #791

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Co-authored-by: davidperezgar <[email protected]>
Co-authored-by: mukeshpanchal27 <[email protected]>
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[swissspidy]

Can we do PHP 8.0+ instead? Would be more reasonable for a developer tool like this

[ernilambar]

Can we do PHP 8.0+ instead? Would be more reasonable for a developer tool like this

Directory run in 7.4 I guess. It wont be feasible to run PCP in the directory if we bump to 8.0 now.

[mukeshpanchal27]

Per https://wordpress.org/about/stats/, After these PR get merged the total ~11.14% sites are not able to use PCP.

Version	Usage
7.3	3.30%
7.2	2.78%
7.1	0.70%
7.0	1.12%
5.6	2.28%
5.5	0.26%
5.4	0.31%
5.3	0.39%
5.2	0.17%

[ernilambar]

Since this is developer targeted plugin, we may not have to stick with core's PHP philosophy, I guess.