Add caching for remote tasks fetched

[chmouel]

in #1371 we optimize the resolving only to the matched PipelineRuns which saves calls to github api and remote servers..

but for the matched ones when we have the same URL we will fetch again and again the remote task if there is multiple PRs matched (ie: git-clone)

we should optimize this by adding a cache that is lock free (i.e in context) and not fetched twice in the same run..

Originally posted by @sm43 in https://github.com/openshift-pipelines/pipelines-as-code/issues/1371#issuecomment-1699056239