[Feature] Set Executor Instances limits dynamically from properties (#2193)

* Update 'ProcessExecutor.java' to use dynamic process limits from properties

* Move limits location out of 'application.properties'

* Rename 'SemaphoreLimit' to 'SessionLimit' and bundle with 'Timeout...' into one parent class

src/main/resources/settings.yml.template

@@ -102,3 +102,22 @@ metrics:
 AutomaticallyGenerated:
   key: example
   UUID: example
+
+processExecutor:
+  sessionLimit:    # Process executor instances limits
+    libreOfficeSessionLimit: 1
+    pdfToHtmlSessionLimit: 1
+    ocrMyPdfSessionLimit: 2
+    pythonOpenCvSessionLimit: 8
+    ghostScriptSessionLimit: 16
+    weasyPrintSessionLimit: 16
+    installAppSessionLimit: 1
+    calibreSessionLimit: 1
+  timeoutMinutes:    # Process executor timeout in minutes
+    libreOfficetimeoutMinutes: 30
+    pdfToHtmltimeoutMinutes: 20
+    pythonOpenCvtimeoutMinutes: 30
+    ghostScripttimeoutMinutes: 30
+    weasyPrinttimeoutMinutes: 30
+    installApptimeoutMinutes: 60
+    calibretimeoutMinutes: 30