Failed to get_keyword_names!

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hi Team,
I try to run skuliLibrary framework under a docker file.
The scenarios is as follow:
1.Create a docker file
```
FROM node:14-alpine

RUN apk update \

&& apk add build-base python3

RUN mkdir /.npm \
&& chmod 777 /.npm

RUN apk add --update py3-pip
RUN apk add openjdk11
# CHROME
RUN apk --no-cache upgrade && apk add --no-cache chromium chromium-chromedriver
RUN apk add libexif udev

# ROBOT + LIBRARIES
RUN pip3 install robotframework && pip3 install robotframework-selenium2library && pip3 install robotframework-jsonlibrary && pip3 install robotframework-jsonlibrary && pip3 install robotframework-SikuliLibrary

RUN apk update && apk add bash

ENTRYPOINT ["/bin/terraform"]
```
2. docker build to build the image
3. docker run -it -d -P robotfram ==>-P option to forword all ports to the host machine which is a windows machine
4. docker cp "C:\Users\nboujelben\Downloads\test" sleepy_goodall:/home==>copy the test folder from local to my container
5. my test file named robot.test and it contains a simple example:
```
*** Settings ***
Documentation Sikuli Library Demo
Library Selenium2Library
Library SikuliLibrary
Test Setup Run Keywords Start Sikuli Process AND Initialize all images
Test Teardown Stop Remote Server

*** Keywords ***
Initialize all images
Add Image Path ${CURDIR}\\img
Login to Browser with download preferences
[Documentation] This one is without specifying download location

Open Browser https://www.docdroid.net/ chrome #options=add_argument("--no-sandbox");add_argument("--headless");add_argument("--disable-dev-shm-usage")
Maximize Browser Window
Click Element id=select
SikuliLibrary.Input Text path.png ${CURDIR}\\img\\signature.jpeg
Press Special Key ENTER

*** Test cases ***
Sikuli tests
Log ToConsole ${CURDIR}
Login to Browser with download preferences

```

6.docker exec -it 2305c31c6cd7 /bin/sh ==>i connect to my container
7.export DISPLAY=127.0.0.1:10.0 ==>create an env variable named DISPLAY
8. apk add opencv-dev
apk add tesseract-ocr
8. run a test as folow robot test.robot
9. I get this erreur:
```
/home/test # robot test.robot
==============================================================================
Test :: Sikuli Library Demo
==============================================================================
[ WARN ] Test get_keyword_names failed! Connecting remote server at http://127.0.0.1:55781/ failed:
[ WARN ] Test get_keyword_names failed! Connecting remote server at http://127.0.0.1:55781/ failed:
Sikuli tests | FAIL |
Setup failed:
Failed to get_keyword_names!

Also teardown failed:
AttributeError: 'NoneType' object has no attribute 'run_keyword'
------------------------------------------------------------------------------
Test :: Sikuli Library Demo | FAIL |
1 test, 0 passed, 1 failed
==============================================================================
Output: /home/test/output.xml
Log: /home/test/log.html
Report: /home/test/report.html
```

Start with the Docker setup in the issue and the SikuliLibrary remote server used by `test.robot`; reproduce the failure by running `robot test.robot` in the container. Trace the `get_keyword_names` failure at the reported remote-server endpoint and verify that the test setup and teardown complete without the reported errors.

Written by the indexing model from the issue text.