BitBucket: Facing issue with SSH key for repo

Below is the error message displayed while push in origin master

conq: repository access denied. deployment key is not associated with the reques
ted repository.
fatal: Could not read from remote repository.
Please make sure you have the correct access rights
and the repository exists.

One of the best solution provide here

Install Maven on Linux or Unix system by command line

Steps to install Maven on Linux or Unix machine:

1. Open Maven binaries from link
2. Pick the latest one for 
Eg. http://mirror.olnevhost.net/pub/apache/maven/binaries/apache-maven-3.2.2-bin.tar.gz
3. Navigate to /usr/local/maven Type command 
  $ wget http://mirror.olnevhost.net/pub/apache/maven/binaries/apache-maven-3.2.2-bin.tar.gz
4. Type command to extract the tar file. 
   $ tar xvf apache-maven-3.2.2-bin.tar.gz
5. Add environment variable-

   $ export M2_HOME=/usr/local/maven/apache-maven-3.2.2

$ export M2=$M2_HOME/bin

$ export PATH=$M2:$PATH

6. Check if Maven is install by below command -
$ mvn -version

[EDIT-Install straight forward with single command]
sudo apt install maven

Demo Practice website for Selenium Automation Testing

Here are some demo sites for learning Selenium Automation Testing using Selenium IDE or Selenium RC (Selenium Remote control) or Selenium Webdriver.

E-commerce website - http://store.demoqa.com/
Basic fields demo portal - http://demoqa.com/
Automation demo web page practice - http://toolsqa.com/automation-practice-form/
Switch window - http://toolsqa.com/automation-practice-switch-windows/
Handling browsers alerts - http://toolsqa.com/handling-alerts-using-selenium-webdriver/
iFrame practice - http://toolsqa.com/iframe-practice-page/