WIP: Add vcard/ical support (#1504)

* Initial from-ical implementation

* Initial from-vcard implementation

* Rename from-ics and from-vcf for autoconvert

* Remove redundant clones

* Add from-vcf and from-ics tests

Co-authored-by: Jonathan Turner <jonathandturner@users.noreply.github.com>

crates/nu-cli/tests/format_conversions/mod.rs

@@ -1,6 +1,7 @@
 mod bson;
 mod csv;
 mod html;
+mod ics;
 mod json;
 mod markdown;
 mod ods;
@@ -9,5 +10,6 @@ mod ssv;
 mod toml;
 mod tsv;
 mod url;
+mod vcf;
 mod xlsx;
 mod yaml;