Fix .nvmrc file path (#36)

### What was the problem?

This PR resolves LISK-944.

### How was it solved?

File path for `.nvmrc` was fixed when reading this file.

scripts/installApplication.sh

@@ -2,7 +2,6 @@
 
 # Install application
 app_dir_name=/home/ubuntu/lisk-across-relayer
-mkdir $app_dir_name
 cd $app_dir_name
 echo "Current DIR: $PWD"
 yarn install --frozen-lockfile

scripts/installDependencies.sh

@@ -1,19 +1,28 @@
-# Install nodejs dependencies
-echo "Current DIR: $PWD"
+#!/bin/bash
 # Script to install Node.js using NVM on Ubuntu
 
+app_dir_name=/home/ubuntu/lisk-across-relayer
+cd $app_dir_name
+echo "Current DIR: $PWD"
+
 # Read node version from .nvmrc file
 node_version=$(cat .nvmrc | tr -d "\n")
+if [[ -z "${node_version-}" ]];
+then
+    echo ".nvmrc not found; exiting..."
+    exit 1
+fi
 
 # Function to install NVM
 install_nvm() {
     curl -o- https://raw.githubusercontent.com/nvm-sh/nvm/v0.40.0/install.sh | bash
 }
 
 install_node_version() {
+    # Setting up environment for NVM    
+    export NVM_DIR="$([ -z "${XDG_CONFIG_HOME-}" ] && printf %s "${HOME}/.nvm" || printf %s "${XDG_CONFIG_HOME}/nvm")"
+
     # Check if NVM is installed
-    export NVM_DIR="$HOME/.nvm"
-
     if [ -s "$NVM_DIR/nvm.sh" ];
     then
         echo "NVM is already installed."
@@ -22,19 +31,18 @@ install_node_version() {
         install_nvm
     fi
 
-    # Setting up environment for NVM    
-    export NVM_DIR="$([ -z "${XDG_CONFIG_HOME-}" ] && printf %s "${HOME}/.nvm" || printf %s "${XDG_CONFIG_HOME}/nvm")"
-    [ -s "$NVM_DIR/nvm.sh" ] && \. "$NVM_DIR/nvm.sh" # This loads nvm
-
+    # Load NVM
+    [ -s "$NVM_DIR/nvm.sh" ] && \. "$NVM_DIR/nvm.sh"
+
     echo "Installing Node version $node_version..."
     nvm install $node_version
 }
 
 install_node_version
-
 echo "Node.js version $node_version has been installed."
 
 # Install yarn
 npm install --global yarn
+
 # Install pm2
 npm install --global pm2@latest