Use ReadOnlySpan<char> on RegexCompiled engine.

[joperezr]

Contributes to #59629

Related: #59629 and #62222

Using ReadOnlySpans on FindFirstChar for RegexCompiled engine

cc: @stephentoub@danmoseley

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Issue Details

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Contributes to #59629

Related: #59629 and #62222

Using ReadOnlySpans on FindFirstChar for RegexCompiled engine

cc: @stephentoub@danmoseley

Author:	joperezr
Assignees:	-
Labels:	area-System.Text.RegularExpressions
Milestone:	-

[danmoseley]

Stephen should probably review, but should _runtextLocal / runtextLocal become a span also?

[stephentoub]

Stephen should probably review, but should _runtextLocal / runtextLocal become a span also?

_runtextLocal should go away once Go is updated as well, but it's used there as a string and so can't be removed / changed until Go is addressed.