HPackDecoderTest.testTooBigToIndex() has bad assumption on Host header value

**Jetty version(s)**
9.4.x+

**Java version/vendor** `(use: java -version)`
All

**OS type/version**
All

**Description**
See: https://github.com/eclipse/jetty.project/blob/jetty-10.0.x/jetty-http2/http2-hpack/src/test/java/org/eclipse/jetty/http2/hpack/HpackDecoderTest.java#L251

https://github.com/eclipse/jetty.project/blob/b8b32d0fdd0286bb212b4deccb61474d72fe280e/jetty-http2/http2-hpack/src/test/java/org/eclipse/jetty/http2/hpack/HpackDecoderTest.java#L251

A Host on an authority cannot contain spaces like it's validating in the assumption.