Update crabstone requirement from ~> 4 to >= 4, < 6

[dependabot[bot]]

Updates the requirements on crabstone to permit the latest version.

Release notes

Sourced from crabstone's releases.

v4.0.3

• Fix Instruction class redefinition (#12)
• Drop Travis and use Github action

Changelog

Sourced from crabstone's changelog.

4.0.3

• Fixed Instruction class redefinition (#12)
• Diff from previous release

4.0.2

• Supported binding Capstone 4.0.2
• Raised errors when the version of libcapstone is not supported
• Internal refactors and code cleanup
• Diff from previous release

4.0.0

• Supported both Capstone 3.x and 4.x.
• Supported 4 new architectures: M68K, M680X, TMS320C64x, and EVM.
• Added cs_regs_access API (wrapped as Instruction#regs_access in Crabstone).
• Changed some internal constants and methods.
• Fixed tons of bugs.
• For more details, see david942j/crabstone#2

3.0.3-rc1

• Internal binding updates, updated some test specs.

3.0

• See https://github.com/aquynh/capstone/wiki/ChangeLog-since-3.0-rc3
• Shouldn't be breaking, most changes are internal.

3.0rc3

• Generic groups ( CS_GRP_JUMP, CS_GRP_CALL etc)
• Mips 32R6 + MICRO
• Many constant changes
• PPC CRX operand
• X86: added prefixed symbols
• THIS IS A BREAKING CHANGE ( even from rc1 )

3.0rc1

• Update for C side changes
• Add support for Xcore
• ARM, ARM64 and X86 passing, rest waiting for upstream

2.2.0

• Add support for Sparc and SystemZ

2.1rc1

• Many constant changes
• disasm CAN now return an Array, with a slightly scary built-in finalizer

2.0.1

• Update X86 constants

2.0.0

• Add PPC support

... (truncated)

Commits

• c4d5cad Bump v4.0.3
• ac0eb5a Setup github action (#13)
• 6e9724e Fix Instruction class redefinition (#12)
• 215049a Fix immutable string in python.rb
• 664eae9 Upgrade Rubocop to v1 (#11)
• c3e9f71 Drop Travis (#10)
• a7e3b6f Bump 4.0.2
• 155d26d Test against Capstone 4.0.2 (#7)
• 6d17682 Upgrade dependencies (#8)
• 23059aa Update rake requirement from ~> 12 to ~> 13 (#6)
• Additional commits viewable in compare view

Dependabot will resolve any conflicts with this PR as long as you don't alter it yourself. You can also trigger a rebase manually by commenting @dependabot rebase.

---

Dependabot commands and options

You can trigger Dependabot actions by commenting on this PR:

• @dependabot rebase will rebase this PR
• @dependabot recreate will recreate this PR, overwriting any edits that have been made to it
• @dependabot merge will merge this PR after your CI passes on it
• @dependabot squash and merge will squash and merge this PR after your CI passes on it
• @dependabot cancel merge will cancel a previously requested merge and block automerging
• @dependabot reopen will reopen this PR if it is closed
• @dependabot close will close this PR and stop Dependabot recreating it. You can achieve the same result by closing it manually
• @dependabot show <dependency name> ignore conditions will show all of the ignore conditions of the specified dependency
• @dependabot ignore this major version will close this PR and stop Dependabot creating any more for this major version (unless you reopen the PR or upgrade to it yourself)
• @dependabot ignore this minor version will close this PR and stop Dependabot creating any more for this minor version (unless you reopen the PR or upgrade to it yourself)
• @dependabot ignore this dependency will close this PR and stop Dependabot creating any more for this dependency (unless you reopen the PR or upgrade to it yourself)

---

This change is