Advance deprecation of hex string literals (Error)

[JinShil]

Followup to #7767

Hex strings were deprecated in 2.079. Following typical deprecation proceedings, the deprecation warning should now become an error.

Documentation update: dlang/dlang.org#2617

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[JinShil]

Ocean 5.0.0 was released. Why doesn't buildkite succeed?

cc @mihails-strasuns

[PetarKirov]

[..]
./src/ocean/transition.d(42): Error: basic type expected, not `static`
--
  | ./src/ocean/transition.d(42): Error: found `static` when expecting `)`
  | ./src/ocean/transition.d(42): Error: semicolon expected following auto declaration, not `immutable`
  | ./src/ocean/transition.d(42): Error: declaration expected, not `)`
  | ./src/ocean/meta/types/Qualifiers.d(73): Error: basic type expected, not `static`
  | ./src/ocean/meta/types/Qualifiers.d(73): Error: found `static` when expecting `)`
  | ./src/ocean/meta/types/Qualifiers.d(73): Error: found `immutable` when expecting `)`
  | ./src/ocean/meta/types/Qualifiers.d(73): Error: found `)` when expecting `;`
  | ./src/ocean/meta/types/Qualifiers.d(73): Error: found `)` instead of statement
  | ./src/ocean/meta/types/Qualifiers.d(169): Error: basic type expected, not `static`
  | ./src/ocean/meta/types/Qualifiers.d(169): Error: found `static` when expecting `)`
  | ./src/ocean/meta/types/Qualifiers.d(169): Error: found `immutable` when expecting `)`
  | ./src/ocean/meta/types/Qualifiers.d(169): Error: no identifier for declarator `U`
  | ./src/ocean/meta/types/Qualifiers.d(169): Error: declaration expected, not `)`
  | ./src/ocean/meta/types/Qualifiers.d(173): Error: declaration expected, not `else`
  | ./src/ocean/meta/types/Qualifiers.d(176): Error: unrecognized declaration
  | ./src/ocean/core/Test.d(230): Error: semicolon expected following function declaration
  | ./src/ocean/core/Test.d(232): Error: declaration expected, not `if`

Looks like an error with the D1 to D2 transition support code.
Also CC @leandro-lucarella-sociomantic @mathias-lang-sociomantic @nemanja-boric-sociomantic.

[Geod24]

Fix for ocean: dlang/ci#381

[mihails-strasuns]

Why doesn't buildkite succeed?

Starting with 5.0.0 support of D1 was dropped and it doesn't need to run auto-conversion anymore.

[mihails-strasuns]

Yeah, exactly what @Geod24 has just done :)