feat(#3934): spdx meta instead of <license/> node

[h1alexbel]

In this PR I've removed license as a commentary text from .eo program source, and as the result <license/> node from XMIR. License was replaced with +spdx meta.

closes #3934
History:

• feat(<license/> in XMIR should have SPDX format, instead of raw text #3934): remove license
• feat(<license/> in XMIR should have SPDX format, instead of raw text #3934): off license node
• feat(<license/> in XMIR should have SPDX format, instead of raw text #3934): +spdx
• feat(<license/> in XMIR should have SPDX format, instead of raw text #3934): redundant

[github-actions]

🚀 Performance Analysis

Test	Base Score	PR Score	Change	% Change	Unit	Mode
benchmarks.XmirBench.xmirToEO	170.697	172.842	2.146	1.26%	ms/op	Average Time
benchmarks.XmirBench.xmirToPhi	167.488	186.645	19.157	11.44%	ms/op	Average Time
benchmarks.XmirBench.xmirToSaltyPhi	163.323	164.969	1.646	1.01%	ms/op	Average Time

⚠️ Performance loss: benchmarks.XmirBench.xmirToEO is slower by 2.146 ms/op (1.26%)
⚠️ Performance loss: benchmarks.XmirBench.xmirToPhi is slower by 19.157 ms/op (11.44%)
⚠️ Performance loss: benchmarks.XmirBench.xmirToSaltyPhi is slower by 1.646 ms/op (1.01%)

[h1alexbel]

@maxonfjvipon take a look, please

[maxonfjvipon]

@h1alexbel also you forgot to remove license from XMIR.xsd

[h1alexbel]

@maxonfjvipon updated. Take a look, please (REUSE still expects license to be placed in comments)

[maxonfjvipon]

@h1alexbel any plan how we can fix it?

[h1alexbel]

@maxonfjvipon looks like we should add colon : between License-Identifier meta and identifier itself:

+spdx SPDX-License-Identifier: MIT

[h1alexbel]

@maxonfjvipon updated. Take a look, please