Swift 5.10.1 Release

Adds SPI for a NSRE compatibility mode option (#698) (#702)

NSRegularExpression matches at the Unicode scalar level, but also
matches `\r\n` sequences with a single `.` when single-line mode is
enabled. This adds a `_nsreCompatibility` property that enables both
of those behaviors, and implements support for the special case
handling of `.`.

Swift 5.10 Release

What's Changed

• Update swift/main with recent changes by @milseman in #651
• Update swift main by @milseman in #674
• [swift/main] Optimize search for start-anchored regexes by @natecook1000 in #683
• [5.10] Substring boundaries during matching by @natecook1000 in #697
• [swift/release/5.10] Adds SPI for a NSRE compatibility mode option (#698) by @natecook1000 in #702

Full Changelog: swift-5.9.2-RELEASE...swift-5.10-RELEASE