Extra 'space' between depot/workspace cause unexpected error.

[iakoff]

Description: Extra 'space' symbol between depot and workspace name in $P4_MAPPINGS cause unexpected error.
Steps to reproduce:
export P4CLIENT="SRR_UFS_BILIBQWE_ASD_TSUNAMI"

ensure, that here 2 space char

export P4_MAPPINGS="//PROJECT/BRANCH/... /PROJECT/BRANCH/..."

python3.7 -u -m universum --p4-client ${P4CLIENT} --p4-force-clean -lo file --no-archive --vcs-type p4

==> Universum 0.18.7 started execution

1. Preparing repository
   | ==> Adding file /Launcher/5829/artifact/artifacts/REPOSITORY_STATE.txt to artifacts...
   | 1.1. Connecting
   | â”” [Success]
   |
   | 1.2. Creating workspace
   | | 1.2.1. Cleaning workspace
   | | â”” [Success]
   | |
   | | Error: [P4#run] Errors during command execution( "p4 client -i" )
   | |
   | | [Error]: "Error in client specification.\nMapping '//SRR_UFS_BILIBQWE_ASD_TSUNAMII' is not under '//SRR_UFS_BILIBQWE_ASD_TSUNAMI/...'."
   | |
   | â”” [Failed]
   |
   â”” [Success]

2. Finalizing
   | 2.1. Connecting
   | â”” [Success]
   |
   | 2.2. Cleaning workspace
   | â”” [Success]
   |
   | 2.3. Disconnecting
   | â”” [Success]
   |
   â”” [Success]

==> Universum 0.18.7 finished execution