Update DSP to v0.8

[anowacki]

Do not merge until satisfied that dependents of Seis.jl or packages often used with it that depend on DSP.jl are compatible with v0.8.

Note this implies dropping support for Julia versions before v1.10, since DSP.jl v0.8 only supports Julia v1.10+.

v0.8 of DSP is a breaking change. Update filtering to use the new version and change compatibility to only be compatible with the new version.