[chore][testbed]: add options for retry/storage for filelog (#36781)

This options can be useful for test cases with retry/storage options
enabled.

.chloggen/testbed-add-filelog-retry.yaml

@@ -0,0 +1,27 @@
+# Use this changelog template to create an entry for release notes.
+
+# One of 'breaking', 'deprecation', 'new_component', 'enhancement', 'bug_fix'
+change_type: enhancement
+
+# The name of the component, or a single word describing the area of concern, (e.g. filelogreceiver)
+component: tesbed
+
+# A brief description of the change.  Surround your text with quotes ("") if it needs to start with a backtick (`).
+note: add options for retry/storage for filelog sender
+
+# Mandatory: One or more tracking issues related to the change. You can use the PR number here if no issue exists.
+issues: [36781]
+
+# (Optional) One or more lines of additional information to render under the primary note.
+# These lines will be padded with 2 spaces and then inserted directly into the document.
+# Use pipe (|) for multiline entries.
+subtext:
+
+# If your change doesn't affect end users or the exported elements of any package,
+# you should instead start your pull request title with [chore] or use the "Skip Changelog" label.
+# Optional: The change log or logs in which this entry should be included.
+# e.g. '[user]' or '[user, api]'
+# Include 'user' if the change is relevant to end users.
+# Include 'api' if there is a change to a library API.
+# Default: '[user]'
+change_logs: []

testbed/datasenders/stanza.go

@@ -20,7 +20,9 @@ import (
 )
 
 type FileLogWriter struct {
-	file *os.File
+	file    *os.File
+	retry   string
+	storage string
 }
 
 // Ensure FileLogWriter implements LogDataSender.
@@ -41,6 +43,16 @@ func NewFileLogWriter() *FileLogWriter {
 	return f
 }
 
+func (f *FileLogWriter) WithRetry(retry string) *FileLogWriter {
+	f.retry = retry
+	return f
+}
+
+func (f *FileLogWriter) WithStorage(storage string) *FileLogWriter {
+	f.storage = storage
+	return f
+}
+
 func (f *FileLogWriter) Capabilities() consumer.Capabilities {
 	return consumer.Capabilities{MutatesData: false}
 }
@@ -120,7 +132,9 @@ func (f *FileLogWriter) GenConfigYAMLStr() string {
           layout: '%%Y-%%m-%%d'
         severity:
           parse_from: attributes.sev
-`, f.file.Name())
+    %s
+    %s
+`, f.file.Name(), f.retry, f.storage)
 }
 
 func (f *FileLogWriter) ProtocolName() string {