optimize nearest_neighbor_assosiation

[goktug97]

Vectorize nearest_neighbor_assosiation.
It took avarage 0.02 seconds for 3000->3000 points.

                   -`                    goktug@Goktug
                  .o+`                   -------------
                 `ooo/                   OS: Arch Linux x86_64
                `+oooo:                  Host: 23257R2 ThinkPad X230
               `+oooooo:                 Kernel: 5.3.7-arch1-1-ARCH
               -+oooooo+:                Uptime: 6 hours, 14 mins
             `/:-:++oooo+:               Packages: 1961 (pacman)
            `/++++/+++++++:              Shell: zsh 5.7.1
           `/++++++++++++++:             Resolution: 1366x768
          `/+++ooooooooooooo/`           WM: i3
         ./ooosssso++osssssso+`          Theme: Arc-Dark [GTK2/3]
        .oossssso-````/ossssss+`         Icons: Xenlism-Wildfire-SaturDay [GTK2/3]
       -osssssso.      :ssssssso.        Terminal: st
      :osssssss/        osssso+++.       Terminal Font: Fira Code
     /ossssssss/        +ssssooo/-       CPU: Intel i5-3320M (4) @ 3.300GHz
   `/ossssso+/:-        -:/+osssso+-     GPU: Intel 3rd Gen Core processor Graphics Controller
  `+sso+:-`                 `.-/+oso:    Memory: 2952MiB / 7663MiB
 `++:.                           `-/+/
 .`                                 `/

[coveralls]

Pull Request Test Coverage Report for Build 1061

• 3 of 3 (100.0%) changed or added relevant lines in 1 file are covered.
• 1 unchanged line in 1 file lost coverage.
• Overall coverage increased (+0.03%) to 90.384%

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Files with Coverage Reduction	New Missed Lines	%
PathPlanning/ClosedLoopRRTStar/pure_pursuit.py	1	94.57%

Totals
Change from base Build 1051:	0.03%
Covered Lines:	6730
Relevant Lines:	7446

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💛 - Coveralls

[AtsushiSakai]

@goktug97 Hi. Thank you for your cool PR. Could you please add your name in the header comment?

[goktug97]

@goktug97 Hi. Thank you for your cool PR. Could you please add your name in the header comment?

Thank You, Done

[AtsushiSakai]

@goktug97 Thank you!!. I will merge it.