PR: Fix error when detecting spyder-kernels version

[ccordoba12]

Description of Changes

This fixes the detection of spyder-kernels at startup in our dependencies mechanism.

Issue(s) Resolved

Fixes #15091.

Affirmation

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[Kashish1000]

change SPYDER_KERNELS_REQVER = '>=2.0.1;<2.1.0' to
SPYDER_KERNELS_REQVER = '>=2.0.1'
This will fix this error

[real-yfprojects]

change SPYDER_KERNELS_REQVER = '>=2.0.1;<2.1.0' to
SPYDER_KERNELS_REQVER = '>=2.0.1'
This will fix this error

The <2.1.0 is probably there, so that changes in new versions which aren't backwards compatible are noticed and told the user.
But if they comply to Semantic Versioning the minor version number should not increase in case of backwards incompatible changes. Instead the major (first) version number should increase. The line should changed to

 SPYDER_KERNELS_REQVER = '>=2.0.1;<3.0.0'

[ccordoba12]

@Kashish1000, that's not the right solution.

@real-yfprojects, we know what we're doing.