rune: Remove unwraps in languageserver #1852

Job	Run time
clippy	2m 10s
msrv	1m 30s
docs	3m 16s
nightly	3m 27s
rustfmt	10s
basics	1s
wasm	1m 8s
test_miri (rune)	3m 35s
test_miri (rune-core)	43s
no_std (ubuntu-latest, minimal)	1m 9s
build_feature (alloc)	3m 26s
test_miri (rune-alloc)	6m 7s
test_doc	6m 25s
no_std (macos-latest, minimal)	1m 8s
build_feature (cli)	4m 33s
build_feature (cli,doc)	4m 2s
test_rune	3m 12s
build_feature (cli,fmt)	4m 8s
test_lib	4m 24s
build_feature (doc)	3m 48s
build_feature (workspace)	3m 25s
build_feature (languageserver)	4m 1s
build_feature (byte-code)	3m 22s
build_feature (capture-io)	3m 35s
build_feature (emit)	3m 30s
	1h 16m 15s

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