Update `proc-macro-crate` to `3.1.0`

[Luro02]

The old version caused a conflict with another crate that prevented me from compiling the code.

To prevent future conflicts, it would make sense to only define the major version (minor and patch updates should not break code):

[dependencies]
-syn = { version = "2.0.48", features = ["extra-traits", "parsing"] }
+syn = { version = "2", features = ["extra-traits", "parsing"] }
quote = "1"
proc-macro2 = "1"
-proc-macro-crate = "3.1.0"
+proc-macro-crate = "3"

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