[FAB-9783] Delete unused file install_instantiate.rst
[FAB-9783] Delete unused file install_instantiate.rst

Nothing in the docs directory refers to this file in any way,
so it should be safe to get rid of it.

Change-Id: I02dfb276407e51b11d49c7bc5bbfe64dbf850700
Signed-off-by: Robert P. J. Day <01aa5cd9a29907856ec6ddeebcb643ede4c45b8b@crashcourse.ca>

stemlending/fabric,muralisrini/fabric,jimthematrix/fabric,xixuejia/fabric,manish-sethi/fabric,manish-sethi/fabric-sidedb,muralisrini/fabric,stemlending/fabric,stemlending/fabric,jimthematrix/fabric,manish-sethi/fabric-sidedb,manish-sethi/fabric-sidedb,manish-sethi/fabric-sidedb,muralisrini/fabric,xixuejia/fabric,hyperledger/fabric,manish-sethi/fabric-sidedb,binhn/fabric,xixuejia/fabric,stemlending/fabric,manish-sethi/fabric-sidedb,binhn/fabric,binhn/fabric,hyperledger/fabric,manish-sethi/fabric-sidedb,manish-sethi/fabric