Modify driver invocation on swift run --repl to match new REPL behavior. (#5622)

Behaviour modified in rdar://78280429.

Resolves rdar://95793872

Author: artemcm

Sources/Build/BuildPlan.swift

@@ -2175,7 +2175,7 @@ public class BuildPlan {
     /// importing the modules in the package graph.
     public func createREPLArguments() -> [String] {
         let buildPath = buildParameters.buildPath.pathString
-        var arguments = ["-I" + buildPath, "-L" + buildPath]
+        var arguments = ["repl", "-I" + buildPath, "-L" + buildPath]
 
         // Link the special REPL product that contains all of the library targets.
         let replProductName = graph.rootPackages[0].identity.description + Product.replProductSuffix

Tests/BuildTests/BuildPlanTests.swift

@@ -890,8 +890,7 @@ final class BuildPlanTests: XCTestCase {
             fileSystem: fs,
             observabilityScope: observability.topScope
         )
-        XCTAssertEqual(plan.createREPLArguments().sorted(), ["-I/Dep/Sources/CDep/include", "-I/path/to/build/debug", "-I/path/to/build/debug/lib.build", "-L/path/to/build/debug", "-lpkg__REPL"])
-
+        XCTAssertEqual(plan.createREPLArguments().sorted(), ["-I/Dep/Sources/CDep/include", "-I/path/to/build/debug", "-I/path/to/build/debug/lib.build", "-L/path/to/build/debug", "-lpkg__REPL", "repl"])
         XCTAssertEqual(plan.graph.allProducts.map({ $0.name }).sorted(), [
             "Dep",
             "exe",