Bump version docs to 1.0.0-alpha.1 (#82)

Bump version docs to 1.0.0-alpha.1

### Motivation

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### Modifications

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### Result

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Reviewed by: simonjbeaumont

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#82

README.md

@@ -19,7 +19,7 @@ Add the package dependency in your `Package.swift`:
 ```swift
 .package(
     url: "https://github.com/apple/swift-openapi-runtime",
-    .upToNextMinor(from: "0.3.0")
+    exact: "1.0.0-alpha.1"
 ),
 ```
 

Sources/OpenAPIRuntime/Documentation.docc/Documentation.md

@@ -19,7 +19,7 @@ Add the package dependency in your `Package.swift`:
 ```swift
 .package(
     url: "https://github.com/apple/swift-openapi-runtime",
-    .upToNextMinor(from: "0.3.0")
+    exact: "1.0.0-alpha.1"
 ),
 ```