Lock to prevent concurrent access to model pipeline in playground

[hmartiro]

This should avoid the most basic conflict with multiple users on
the app at one time. Seems to work with initial testing.

Topic: pipeline_lock
Closes: #73

[hmartiro]

Reviews in this chain:
└#97 Lock to prevent concurrent access to model pipeline in playground
　└#96 [WIP] Low Rank Adaptation

[hmartiro]

#	head	base	diff	date	summary
0	1fb91419	e832b92c	diff	Jan 16 18:26 PM	1 file changed, 51 insertions(+), 40 deletions(-)