Rename seq-some-p to seq-some and seq-contains-p to seq-contains

Rename seq-some-p to seq-some and seq-contains-p to seq-contains

* lisp/emacs-lisp/seq.el (seq-some, seq-contains): Rename the functions
  without the "-p" prefix.
* test/automated/seq-tests.el (test-seq-some, test-seq-contains): Update
  the tests accordingly.
* doc/lispref/sequences.texi (Sequence Functions): Update the
  documentation for seq.el.